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The Assessment and Management of Pain

6 Contact Hours including 6 Advanced Pharmacology Hours
Meets Oregon Requirements
This peer reviewed course is applicable for the following professions:
Advanced Practice Registered Nurse (APRN), Certified Nurse Midwife, Certified Nurse Practitioner, Certified Registered Nurse Anesthetist (CRNA), Clinical Nurse Specialist (CNS), Licensed Practical Nurse (LPN), Licensed Vocational Nurses (LVN), Nursing Student, Occupational Therapist (OT), Occupational Therapist Assistant (OTA), Registered Nurse (RN), Registered Nurse Practitioner
This course will be updated or discontinued on or before Tuesday, June 25, 2024

Nationally Accredited

CEUFast, Inc. is accredited as a provider of nursing continuing professional development by the American Nurses Credentialing Center's Commission on Accreditation. ANCC Provider number #P0274.


Outcomes

≥90% of participants will know how to manage pain appropriately.

Objectives

After completing this continuing education course, the participant will be able to meet the following objectives:

  1. Discuss the multidimensional nature of pain.
  2. Discuss the implications of pain on the patient.
  3. Define acute, chronic, nociceptive and visceral pain.
  4. Discuss the assessment and measurement of pain.
  5. Define drug abuse, dependence, tolerance and addiction.
  6. Compare and contrast pharmacological and non-pharmacological methods to manage pain.
  7. Discuss strategies for monitoring pain and the management of pain.
  8. Compare and contrast the assessment and management of pain in special populations, which include infants, children, adults, and geriatric patients.
  9. Discuss clinical conditions and the management of those conditions that have pain as a significant component.
CEUFast Inc. and the course planners for this educational activity do not have any relevant financial relationship(s) to disclose with ineligible companies whose primary business is producing, marketing, selling, re-selling, or distributing healthcare products used by or on patients.

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To earn of certificate of completion you have one of two options:
  1. Take test and pass with a score of at least 80%
  2. Reflect on practice impact by completing self-reflection, self-assessment and course evaluation.
    (NOTE: Some approval agencies and organizations require you to take a test and self reflection is NOT an option.)
Author:    Raymond Lengel (MSN, FNP-BC, RN)

Introduction

Pain is “an unpleasant sensory and emotional experience associated with actual or potential tissue damage or described in terms of such damage.” Nerve stimulation leads to the physical component of pain. Pain results from an injury and may be confined to a discrete area, or it can be generalized in conditions like fibromyalgia. Nerve fibers transmit pain impulses to the brain, where the brain can personalize the pain experience (MedicineNet.com, 2018).

Patients may experience acute, chronic, or cancer pain. Acute pain follows bodily injury and generally disappears as healing occurs. There is identifiable pathology that accounts for the pain. It may arise from operative procedures or tissue trauma associated with an inflammatory process. It may be associated with objective physical signs, such as increased heart rate, blood pressure, and pallor (autonomic nervous system activity), making patients "look" like they are in pain.

Chronic non-malignant pain is pain that lasts for an extended period. There may or may not be known as active pathology to account for the suffering that the individual is experiencing. In contrast to acute pain, chronic pain is rarely accompanied by signs of autonomic nervous system activity (Dahlhamer et al., 2018).

Cancer pain may be acute, chronic, or intermittent. It usually has a definable cause, which is typically related to tumor recurrence or treatment.

Multidimensional Nature of Pain

Pain is a major problem in today’s society. Pain carries consequences across various categories, including ethical, social, economic, and legal arenas. This course will discuss pain management's ethical, social, economic, and legal implications.

In 2016, 50 million adults in the United States had chronic pain, an estimated 20.4 percent of the population (Dahlhamer et al., 2018). These numbers make it easy to understand that pain is one of the most common reasons people seek medical attention. Pain is a common problem in primary care, with about 20% of outpatient visits being for pain issues. Also, persistent pain affects up to 85% of long-term care residents (DHHS, 2018).

Persistent pain is often associated with anxiety, depression, functional impairment, sleep disturbances, disability, and impairment in activities of daily living. The cost of pain to our nation is estimated at between $560 billion and $635 billion annually (DHHS, 2019).

Chronic pain is defined as pain lasting more than three months and may affect any body part. Chronic pain is most frequently caused by back pain (10%), leg/foot pain (7%), arm/hand pain (4.1%), headache (3.5%), and widespread pain (3.6%). Many affected by chronic pain have more than one type of pain.

Acute pain typically has an abrupt onset and is often described as sharp. It is usually caused by events such as a broken bone, surgery, childbirth, dental pain, or burns. Acute pain may last a short period or a few months. The pain dissipates when the underlying cause has healed. When acute pain lasts longer than 3-6 months, it is then termed chronic. Acute pain that is not appropriately treated may lead to chronic pain.

Multiple barriers to effective pain management exist. These include many individuals, families, health care providers, society, and political barriers. The good news is that we have the knowledge and skills to manage most pain effectively. So, what is the problem? Why is unrelieved pain still so prevalent? Knowledge is important. Clinicians, as well as patients, need to be knowledgeable about methods of assessing and managing pain. Knowledge alone rarely changes practice. Efforts must go beyond education alone if pain treatment is to improve.

Pain Theories

Pain theories help clinicians understand the pain and assist in the guidance of the treatment of pain. Pain theories have been around for many years. One of the first pain theories was the Intensive Theory, which Plato created in the 4th century BCE. It defined pain as an emotion that happens when a stimulus is more intense than usual. It has been refined over the years by other scientists/philosophers. The theory suggests that repeated tactile stimulation produces pain.

The Specificity Theory of Pain suggests that certain pain receptors send signals to the brain that create pain awareness. According to the theory, pain is an independent sensation with peripheral sensory receptors, which act in response to damage to drive signals through the nervous system to centers in the brain.

Other theories that came to light in the 1900s include Pattern, Central Summation, Fourth Theory of Pain, and Sensory Interaction Theory.

A more recent theory is the Gate Control Theory. Pain stimulation is transmitted by small, slow fibers that go into the dorsal horn of the spinal cord. The theory states that there is a gate in the spinal cord which controls sensory information through the spinal cord. When there is more pain stimulation, gate blocking is less effective. The gates open when there is a lot of activity in the pain fibers. The gates may be closed when the A-beta fibers are stimulated, which provide a stimulus for mild irritation, such as lightly touching the skin (massage). This gate inhibits the perception of pain.

Also, messages that descend from the brain, such as those in anxiety states or extreme excitement, can affect the opening or closing of the gates.

The Biopsychosocial Model of Pain suggests that pain involves physiological, psychological, and social factors. It suggests that family and culture influence pain perception and the individual’s response to pain.

Definitions of Pain

  • Pain – “An unpleasant sensory and emotional experience associated with actual or potential tissue damage or described in terms of such damage.”
  • Acute pain – Pain that has an abrupt onset and offers a warning of a disease process or a threat to the body.
  • Chronic pain – Pain that lasts beyond the usual duration of time that an insult or injury to the body needs to heal, Pain without apparent biologic value that has lasted beyond the usual tissue healing time (typically at least three months). Some define chronic pain as pain that continues for at least six months.
  • Maladaptive pain – Pain that is not useful and is out of proportion to tissue damage. This type of pain lasts long after tissue healing and is often due to changes in the central nervous system.
  • Adaptive pain – Pain that protects the individual from injury and aids healing after an injury.
  • Allodynia - pain from a stimulus that typically does not cause pain.
  • Hyperesthesia – Increased sensitivity to stimulation.
  • Paresthesia - An unusual sensation often described as burning or prickling and commonly affected the extremities.
  • Visceral pain – Pain from the viscera mediated by stretch receptors. This pain is commonly described as deep, dull, poorly localized and cramping.
  • Nociceptive pain – Pain from threatened or real tissue damage to non-neural tissue caused by the activation of nociceptors.
  • Neuropathic pain – Pain from an abnormal neural activity from an injury, disease process or dysfunction of the nervous system.
  • Mononeuropathy - Neuropathy affecting one nerve.
  • Polyneuropathy – Neuropathy affecting several nerves.

Pain Anatomy and Physiology

Anatomy and physiology are key factors in understanding pain. Primary afferent fibers are involved in the transmission of pain. A-delta and C fibers transmit noxious stimuli from the body’s periphery to the dorsal horn of the spinal cord. The A-delta fibers have a small diameter, are lightly myelinated, and conduct slowly. They transmit rapid, sharp pain. C fibers are small and unmyelinated fibers that conduct slowly, respond to multiple stimuli, and lead to dull, achy pain. If the pain signal is strong enough, it transmits through the dorsal horn to the spinothalamic tract and the spinoreticular tract. These are the ascending tracts to the cerebral cortex, where the stimulus is recognized as pain. When the pain is identified in the cerebral cortex, it descends to the periphery.

The neurons are involved in transmitting pain through the release of substances and neurotransmitters. The excitatory substances that contribute to pain include P, glutamate, prostaglandins, and nitrous oxide. Inhibitory neurotransmitters inhibit or partially inhibit the transmission of pain. Common inhibitor neurotransmitters include glycine, serotonin, norepinephrine, acetylcholine, and gamma-aminobutyric acid (GABA). Medications that are involved in modulating these neurotransmitters help reduce pain.

The Impact of Pain

Pain affects multiple aspects of life. Pain can lead to physiological changes and potentially to physical illness. It can lead to cognitive changes, as many patients with chronic pain suffer from depression and anxiety. Pain can change the way one thinks and acts leading to behavioral changes.

Pain has to potential to affect an individual’s social life. Chronic pain may limit the patient’s desire to interact in social settings. Social consequences of unrelieved pain may include isolation, inability or reduced desire to go to work, and overall reduced quality of life. Expression and reporting of pain can vary by culture. Some cultures have a more stoic attitude to pain, while others may express more emotion toward pain.

The political arena can strongly influence pain in society. The assessment of pain over the last 20 years has focused on eliminating and reducing pain at all costs. This attitude has contributed to the opioid epidemic and many problems for society. In recent years, politicians have been implementing laws to help ensure that pain is adequately assessed and treated with extra caution to prevent medication abuse.

Many regulatory issues surround pain management. Pain management will be optimized when regulatory barriers are limited. It is a challenging venture as regulations and laws must be set to optimally manage pain and deter the abuse, diversion, and illegal use of controlled substances.

Society, including regulations set in the political arena, must change to help ensure that the negative effects and treatment of pain do not lead to further problems in society. Substance abuse/misuse and drug diversion are major problems associated with pain management.

Substance abuse issues are a real concern in the management of pain.

Opioid misuse is estimated in approximately 21 to 29 percent of those prescribed opioids for chronic pain (Vowles et al., 2015). According to the Center for Disease Control (CDC), in the United States, 46 people die each day from an overdose of prescription painkillers. In 2012, health care providers wrote 259 million prescriptions for painkillers (CDC, 2018).

Here are some statistics on opioid misuse:

  • There has been a two hundred percent increase in overdoses from opioids from 2000 to 2014 (Rudd et al., 2016).
  • Of US veterans treated in primary care settings, 4.8 percent of US veterans reported opioid analgesic misuse (Becker, 2019).
  • It is estimated that of those prescribed an opiate, approximately 8 and 12 percent develop an opioid use disorder (Becker, 2019).
  • Research also shows that white individuals account for 88 percent of those who reported non-heroin opioid substance abuse, most of whom lived in rural settings.
  • In 2010, there were 16,650 cases of drug overdose deaths involving opioid analgesics out of approximately 38,000 overdoses. Of the overdose deaths from opioid analgesia, thirty percent also involved benzodiazepines.

It is estimated that it costs 560 to 635 billion dollars per year to pay for the consequence of pain and its management in the United States (Vowles et al., 2015). There are direct medical costs, opioid dependence costs, lost work productivity, legal costs, and psychological effects on the victims of the crimes caused by the opioid abuse. Also, opioid misuse leads to other diseases such as HIV, hepatitis, and sexually transmitted diseases.

Opioids have the potential to provide analgesia and improve function. These benefits must be weighed against the potential risks, including misuse, addiction, physical dependence, tolerance, overdose, abuse by others, drug-to-drug, and drug-to-disease interactions.

Risk factors for opioid analgesic misuse in those who have it prescribed for chronic pain include:

  • History of substance abuse
  • Tobacco use
  • Family history of substance abuse
  • History of legal problems
  • White race
  • Diagnosis of depression or post-traumatic stress disorder
  • Being less than 40 years old (Vowles et al., 2015)

Prescription drug misuse is using prescription medication with a method or intent inconsistent with how it was prescribed. This misuse includes using medication to get high, selling or sharing it with others (diversion), overuse, having multiple prescribers, and concurrent use of alcohol or other illicit substances. Misuse is necessary but not a sufficient criterion for a substance use disorder. Susceptible individuals risk misusing medications that stimulate the brain's reward center, which may include opioid analgesics, stimulants, benzodiazepines, or tranquilizers.

Drug abuse is when drugs are not used medically or socially appropriately. Controlled substances may lead to dependence, either physical or psychological. After the rapid discontinuation of the substance, physical dependence transpires when there are withdrawal symptoms such as anxiety, tachycardia, hypertension, diaphoresis, a volatile mood, or dysphoria. Psychological dependence is the perceived need for a substance. It makes the person feel as though they cannot function if they do not have the substance. Psychological dependence often kicks in after physical dependence wears off. It typically lasts much longer than physical dependence and often is a strong contributing factor to relapse.

Addiction is psychological dependence and extreme behavior patterns associated with the drug. At this point, there is typically a loss of control regarding drug use. The drug is continued despite serious medical and social consequences. Tolerance, increasing doses of the medication needed to produce an equivalent effect, is typically seen by the time addiction is present. Physical dependence can occur without addiction. Individuals who take chronic pain medication may be dependent on the medication but not addicted.

Addiction is a major concern in those taking opioids. When opioids are prescribed, it is important to determine who is likely to participate in aberrant drug-related behaviors. This behavior may occur in those with major depression, psychotropic medication use, younger age, or those with a family or personal history of drug or alcohol misuse. Those at high risk for addiction should likely be managed with a specialist.

Aberrant behaviors may include abuse, misuse, or addiction. Examples of aberrant drug-related behaviors include requests for early refills, not taking medications as prescribed, failure to keep appointments, visits in distress, frequent reports of lost medication, using multiple prescribers, positive urine drug tests for illicit substances, altering prescriptions, resistance to referrals, resistance to providing prior medical records, resistance to change in therapy, increasing the dose without telling the prescriber, or requests for specific drugs.

The federal government has an important role in combating substance abuse. They are responsible for supporting states and providing tools, data, and guidance to help health care providers prescribe safely. Increased access to mental health care and substance abuse treatment programs will reduce the risk and consequences of substance abuse. The government can also work to increase access to naloxone for first responders. Many states, including Oregon, have prescription drug monitoring programs. Health care providers need to ensure that they are using these drug monitoring programs to find patients who misuse prescriptions and place them at risk of overdose.

Multiple factors are associated with a risk of overdose death. Some factors include using four or more prescribers, using four or more pharmacies, and getting more than 100 morphine equivalents per day (Gwira-Baumbladd et al., 2014).

In addition to opioids, other medications are associated with the misuse. These include stimulants, sedatives, hypnotics, and others. The use of stimulants has increased over recent years. Abuse is most common in those 18-25 years old. Over one million people are estimated to misuse prescription stimulants each year (NIDA, 2018). It is estimated that 5% to 10% of high school students and 5% to 35% of college students misuse stimulants (Clemow, 2014).

Stimulants can cause tachycardia, high blood pressure, increased body temperature, reduced appetite, anxiety, sleep, agitation, and paranoia. Overdose stimulants may lead to agitation, tremor, confusion, anxiety, delirium, mydriasis, hyperreflexia, aggressiveness, hallucinations, paranoia, seizures, and movement disorders (Psychology Today, 2017).

Risk factors for abuse of stimulants include white race, past-month use of cannabis, grade point average of less than 3.5, being a member of a fraternity or sorority, and one episode or more of binge drinking in the last two weeks. In 2018 of those 12 and older, 6.4 million people misused prescription tranquilizers or sedatives over the past year (approximately 2.4 percent of the population). The combination of sedatives and hypnotics, especially with alcohol or opioids, is often the cause of overdose death (SAMSHA, 2019).

Risk factors for nonmedical use of tranquilizers and sedatives include white race, female, panic symptoms, cigarette use, illicit drug use, alcohol abuse, unemployed, and uninsured.

Policies Related to Pain Control

The Joint Commission (JC) recognizes pain control is an important part of quality health care. They acknowledge that pain is the fifth vital sign and should be assessed with other vital signs. According to the JC, patients have the right to assess and treat pain. Other beliefs of the JC include:

  • Patients should be educated about pain.
  • Providers must be competent in the assessment and treatment of pain.
  • Pain should not interfere with function.
  • Managing pain should be included in the plan to discharge a patient.

The State of Oregon has multiple initiatives to ensure proper pain management. The Oregon Pain Management Commission was created to enhance the management of pain. The Commission makes recommendations, provides education, and is involved in research and policy to improve pain control. In the State of Oregon, many health care providers (e.g., nurses, physicians, physician assistants, acupuncturists, podiatrists, chiropractors, naturopaths, psychologists, etc.) are required to take a pain management course. The pain education must include seven hours of pain management education, and it must include one hour that the Oregon Pain Management Commission provides.

The Oregon Medical Board desires effective pain control, which includes the use of specialists, adequate record keeping, coordination of care, and the use of the Prescriptions Drug Monitoring Program. The Prescription Drug Monitoring Program is a database that tracks dispensing and prescribing of controlled substances to patients. It helps health care providers identify patients at high risk of abusing medications.

In 2009, Oregon Senate Bill 355 created a Prescription Drug Monitoring Program for all Schedules II, III, and IV controlled substances dispensed to Oregon residents. Authorized health care providers can only access information to patients under their care.

In 2014, Senate Bill 470 went into effect in Oregon. It made multiple changes to Oregon Senate Bill 355, including it allowed staff members of prescribers and pharmacists to access the Prescription Drug Monitoring Program, allowing prescribers in neighboring states to access the system if they are treating residents of Oregon, allowing public health officials to use de-identified data from the system and allowed prescribers to review prescriptions under their DEA number.

The Intractable Pain Treatment Act, passed in 1995, aims to improve pain control but provides immunity to prescribers for prescribing opioids to those with intractable pain. In 2008, the state of Oregon removed the term Intractable Pain from the Act so that the Act could be applied to a wider range of pain.

In 1997, Oregon implemented the Oregon Death with Dignity Act. It allows terminally ill adults to self-administer lethal doses of medications they obtained via prescription from their physician (Oregon Health Authority, 2020).

In 1998, the Oregon Medical Marijuana Act was passed. This act allows Oregon residents who have a recommendation from their physician to use, cultivate, or possess marijuana. Conditions that are allowed under this act include cancer, HIV/AIDS, severe pain or nausea, post-traumatic stress disorder (PTSD), a degenerative or pervasive neurological condition, glaucoma, seizures, and persistent muscle spasms (Oregon Health Authority, 2019).

Ethics and Pain

Multiple ethical issues surround pain and its management. Health care providers should attempt to minimize pain and suffering while maintaining a balance between adequate pain management and minimizing harm from pain treatment. The health care provider must do no harm and guard against overmedicating the patient. The health care provider must be aware of the negative consequences of pharmacotherapy, including physical dependence, tolerance, and abuse.

Some think that pain management is a human right. Medical organizations do not consider pain management an explicit duty of the prescriber, except for a part of good medical care. If pain control is considered a human right, it will force the government into the middle of the patient-physician relationship.

Access to health care is not equitable and brings up questions of justice. Certain populations are at a disadvantage when it comes to access to pain management. Individuals who do not have insurance may lack the means to receive medical care and pain management. Individuals more likely to have access to care include those older, those who live in a suburb, those who have insurance, those who have a college degree or a high income. Those with less access to care include those with financial problems and those of Hispanic ethnicity (Access and Disparities in (Access to Health Care, 2018).

Ethical issues surround the end of life care. The management of pain at the end of life is a moral duty for the provider caring for a terminal patient. While opioid use may suppress respiration and may even hasten death, treating pain is an important part of care for intractable pain as death nears. The goal of giving pain management is to relieve suffering, not to accelerate death. Palliative sedation may be considered to manage refractory pain at the end of life.

Pain Assessment and Measurement

The assessment of a pain patient is a critical aspect of the proper management of pain. It requires a team approach. The physician or advanced level provider relies on other support personnel such as nurses, nurses’ aides, and therapists to assess the patient properly.

Complex patients require a full assessment, including pain characteristics, the impact of pain on functional status, treatment history, past pain experiences, and how it affects the patient’s psychological state, including relationships.

When and How Should Pain Intensity be Assessed?

Basic pain assessment is simple and must be performed regularly. Action needs to be planned based on the patient’s report of pain.

It makes no difference whether patients are in the hospital, a long-term care facility, a behavioral health facility, an outpatient clinic, or being cared for by a home care agency. No matter where patients are, the intensity of pain should be assessed and documented:

  1. During the initial evaluation of the patient
  2. After any known pain-producing procedure
  3. With each new report of pain
  4. At regular intervals, when vital signs are taken
  5. At suitable intervals after pharmacologic (45-60 minutes after the oral intervention; 15-30 minutes after parenteral intervention) or non-pharmacologic intervention to evaluate the current pain treatment plan

Measuring the severity of pain is often done on scales. Pain scales are meant to compare the intensity of the patient’s pain at different points, not to compare one person’s pain to another. The use of pain scales assists the health care provider in determining the effectiveness of pain treatment.

The best scales are brief, valid, require minimal training to use, and use both behavioral and descriptive measures of pain. When selecting a scale, it is important to consider which scale would work best for the individual patient.

A "0 to 10" numerical scale is the most widely used measure to assess pain intensity. When using the Numerical Rating Scale (NRS), patients are asked to rate their pain from 0 to 10, with "0" equals no pain and "10" equals the worst possible pain they can imagine.

Another scale allows the patient to rate their pain as “no pain, mild pain, moderate pain, severe pain, or unbearable pain." Pain maps can be used for those who have a difficult time speaking. In a pain map, there is a front and rear view of the body on a piece of paper, and the patient draws on the location of the pain and may rate the severity of the pain.

Since we have no instrument to objectively measure pain intensity in the same way that a sphygmomanometer measures blood pressure, the only valid measure of pain is the patient´s self-report (a subjective measure). Sometimes healthcare providers may believe they are the best judges of a person´s pain; however, healthcare providers often over or underestimate a patient´s pain.

pain_chart

For patients who are NOT cognitively impaired but cannot respond verbally or rate their pain numerically, faces scales with happy faces representing no pain (0) and progressively sadder faces representing increasing pain intensity may be used. The patient is asked to choose the face that best depicts their feelings.

Once Current Pain Intensity is Assessed, then What?

Besides current pain intensity, the complete pain assessment includes the following:

  1. Location of pain.
  2. Pain intensity for the worst pain, the best pain gets, and the acceptable pain level. Satisfactory pain relief is a level of pain that may be noticeable but not bothersome.
  3. Character or quality of pain. The words used by the patient to describe pain may enhance the understanding of the etiology of the pain and provide usefulness in selecting interventions to manage it. For example, somatic (musculoskeletal) pain is usually localized and described as dull, achy, and sore. Visceral pain is usually poorly localized and described as cramping or squeezing. Descriptors of burning, shooting, or knife-like are indicative of neuropathic (nerve) pain. (Refer to Table 1).
  4. Onset, duration, variations, and pattern (is the pain better or worse at certain times, certain hours?).
  5. Alleviating factors – what makes the pain better?
  6. Aggravating factors – what makes the pain worse?
  7. Impact of pain on quality of life and daily functioning. How does the pain affect sleeping, relationships with others, mood, emotions, concentration, for example?
Table 1
Pain TypeDescriptionEtiologyTreatment
Neuropathic
  • Burning
  • Shooting
  • Tingling
  • Numbness
  • Radiating
  • Nerve involvement
  • Tumor
  • Postherpetic neuralgia
  • Diabetic neuropathy
  • Post-stroke pain
  • Antidepressants
  • Anticonvulsants
  • Local anesthetics
  • Opioids
NOCICEPTIVEVisceral
(poorly localized)
  • Squeezing
  • Cramping
  • Pressure
  • Distention
  • Deep
  • Tumors occupying:
    • liver
    • pancreas
    • spleen
    • abdominal or thoracic surgery
    • ascites
  • Non-opioids
  • Acetaminophen
  • NSAIDs
  • Opioids
  • Co-analgesics
  • Corticosteroids
  • Local anesthetics
  • Bisphosphonates

NOCICEPTIVE

Somatic
(well-localized)

  • Dull
  • Achy
  • Throbbing
  • Sore
  • Bone metastases
  • Musculoskeletal injury
  • Mucositis
  • Skin lesions
  • Non-opioids
  • Acetaminophen
  • NSAIDs
  • Opioids
  • Co-analgesics
  • Corticosteroids
  • Local anesthetics
  • Bisphosphonates

It is also important to document pain's impact on quality of life. Key questions to ask include:

  • Does pain affect sleep?
  • Does the pain lead to mood alterations?
  • Does the pain lead to reduced energy?
  • Does the pain reduce the patient’s ability to participate in activities and socialize?
  • Does the pain affect relationships?
  • Does the pain limit or affect activity or exercise?
  • Can the patient participate in daily living activities such as bathing, dressing, feeding, toileting, or brushing their teeth?
  • Does the pain impact instrumental activities of daily living (IADL), such as the use of the telephone, doing the laundry, handling of medications, or ability to handle the finances? This impact is less important in the nursing home setting as many of the IADLs are impaired at baseline, which is why there was nursing home placement.

Understanding how pain was treated in the past for the patient will help the clinician treat the current pain. Reviewing past medical records will help the pain management team evaluate the condition. Reviewing all previous history, diagnostic testing, treatment options, and efficacy will help the team make an accurate diagnosis and manage pain appropriately. Certain treatment modalities, including specific medications, are often more effective in one individual when compared to another based on individual genetic variations.

Understanding all medical and surgical conditions can help assure proper pain management. A chronic disease may have a strong impact on the management of pain. Chronic kidney disease, for example, can affect how drugs are excreted. Using non-steroidal anti-inflammatory medications can lead to kidney failure in those with chronic kidney disease.

A mental health evaluation can help the clinician understand the best pain management. Mood or cognitive disorders can affect the way the pain is managed. Chronic pain will likely never be adequately managed if mental illness is not appropriately identified and managed. A history of drug abuse is important to ascertain, as this could profoundly affect how chronic pain is treated.

Personal characteristics may have a strong effect on pain management. Factors influencing pain include race, age, culture, religion, sex, or language.

A review of the patient’s perception of pain is important. Why does the patient believe they have persistent pain? Does the patient feel there was adequate workup done on their condition? What does the patient expect from the treatment, and what are the patient’s goals? Also, psychological factors that contribute to the pain should be assessed. This action will help assess the patient’s expectations. Patients need to have realistic expectations about pain management.

A complete physical exam is an essential part of the management of pain. It is important to have a baseline examination, so subsequent evaluations will allow the health care team to determine progress in pain management and functional capacity.

The physical exam should include a detailed neurological exam, including the patient’s ambulation ability. While exams may include general observations, exams may be focused according to the presenting condition. Observing hygiene, posture, dress, and appearance is important. Those with severe pain will often have poor hygiene, unkempt dress, and appear to be in pain. Observe for any splinting, which may suggest a painful body part. Assessing skin and joints for redness, swelling or deformities helps determine the location and etiology of pain. An abdominal exam for any tenderness or distention should be done. Also, checking joints for a range of motion is an important part of the physical exam in chronic pain. The exam should evaluate functional capacity, strength, endurance, and any pain-related limitations.

Ongoing monitoring of the efficacy and effectiveness of the implemented plan is important. Utilizing similar assessment tools, the health care provider can document the effectiveness of the pain management plan on the patient, which will include any improvement in the quality of life.

Diagnostic Tests

Diagnostic testing can help evaluate painful conditions. It is important to realize that an abnormal diagnostic test does not confirm the source of the pain. Blood tests can be helpful in some conditions to determine or monitor certain causes of pain. For example, an elevated C-reactive protein or an erythrocyte sedimentation rate may be seen in those with polymyalgia rheumatica, infection, or rheumatoid arthritis (all conditions that may cause pain).

Imaging may be necessary for some situations of chronic pain. X-rays, computed tomography, and magnetic resonance imaging can help define the etiology of the pain. Caution must be utilized when imaging, as many abnormalities may be seen in imaging tests that are not the source of the pain.

An electromyogram (EMG) or nerve condition studies are often done to assess the cause of pain. The EMG measures the electrical activity of the muscle and can help find damaged muscle, nerves, or neuromuscular abnormalities such as a herniated disc or myasthenia gravis. The nerve conduction study measures the ability of the nerves to send electrical signals and can help diagnose carpal tunnel syndrome or other neuropathies.

Management of Pain

The goals of pain management are not necessarily complete pain relief. They may include a reduction in the amount of pain, improved quality of life, improved physical and psychological functioning, improved ability to work, improved ability to function in society, and reduced health care utilization.

A pain management plan is more than just a prescription for pain medication. In addition to pharmacotherapy, it should include psychological and physical modalities to manage pain. It should be modified when interventions are not effective.

The patient should be provided with education regarding the plan. It should include information about medications prescribed, other treatment options, and methods to contact the pain management team.

When developing a treatment plan, there are many considerations. The type of pain should be considered. Also, the effect of pain on lifestyle, including psychological, social, and biological components of life, should be considered.

Many factors affect the success of the treatment plan. Issues related to the patient, such as their ability to understand and apply the management plan, will help determine the plan's success. The patient’s willingness to implement the whole plan can profoundly affect the plan's success. If a patient is willing to take a pill but not willing to work on non-pharmacologic interventions (such as physical therapy or weight loss), the plan will lose its effectiveness.

Chronic pain management is a vexing problem that can lead to frustration in the health care provider due to unrealistic expectations of the patient and frustration in the patient due to continued pain. The clinician has the responsibility to manage pain as best as they can because proper pain treatment can significantly improve the quality of life.

General physicians lack training in the management of pain (Loeser & Schatman, 2017). Referral to a pain management specialist may be indicated for those with debilitating symptoms, those needing increased doses of pain medications, those who are non-responsive to treatments, or those with symptoms at multiple sites.

Caregiver or health care provider issues often affect the pain management plan. Many caregivers and health care providers do not accurately comprehend the patient’s pain and may hold false beliefs regarding pain management. Caregivers and health care providers may be inhibited by fear of side effects from medications or concerns of drug addiction, so they may withhold medication from those in pain. Also, caregivers/health care providers and patients may have discordant goals.

Controlled substances should be prescribed for a legitimate medical purpose with careful consideration of the patient’s safety, therapy goals, and treatment efficacy. Treatment of pain should include pharmacotherapy and physical and psychological therapies.

Non-pharmacological Therapy

Numerous non-pharmacologic therapies are used in the management of pain. These may include a combination of physical and psychological techniques. Some methods used other than medications include: physical therapy, exercise, massage, ultrasound therapy, heat/cold application, chiropractic manipulation, psychotherapy, biofeedback, relaxation therapy, acupuncture, transcutaneous electrical nerve stimulation (TENS), music therapy, injections, neuromodulation, spinal cord stimulation, deep brain stimulation, and radiofrequency ablation of nerve tissue.

For those with pain, a physical or occupational therapy trial can be helpful. With the help of a physical therapist, the use of exercises targeting a specific type of pathology can be helpful in the management of pain. Occupational therapists can help recommend devices that can assist in enhancing the activities of daily living.

Massage is soothing and relaxing, both physically and mentally. Massage may decrease pain by relaxing muscle tension and increasing capillary circulation, thereby improving general circulation. A vibration is a form of electric massage. When vibration is applied lightly, it may have a soothing effect like a massage. Vibration applied with moderate pressure may relieve pain by causing numbness, paresthesia, or anesthesia of the area stimulated.

Heat and cold therapies can assist in the management of pain. Heat reduces inflammation and promotes relaxation. It can be in hot tub baths, heating pads, or heat packs. Cold is often more effective in relieving pain than heat. The application of cold reduces muscle spasms secondary to underlying skeletal muscle spasms, joint pathology, or nerve root irritation. Cold application methods include ice massage, ice bags, and gel packs. Alternating heat and cold may be more effective than using either alone.

Multiple psychological techniques can aid in reducing pain. The basis for using these methods is that thought influences feelings, and if thought (and behaviors) can be changed, so can feelings and even sensations, such as pain. Cognitive-behavioral methods require the patient’s active participation.

Relaxation is a state of relative freedom from anxiety and skeletal muscle tension, a quieting or calming of the mind and muscles. Although relaxation is a learned technique, it can be achieved quickly in a motivated patient.

Imagery/visualization involves mentally creating a picture by using one’s imagination. This imagery may focus on a close person, a place of enjoyment, a past event, or anything thought to bring pleasure. Since the mind is occupied, the pain is reduced.

Distraction from pain is the focusing of attention on stimuli other than the pain sensation. The stimuli focused upon can be auditory, visual, or tactile-kinesthetic (hearing, seeing, touching, and moving). By focusing attention and concentration on stimuli other than pain, pain is placed on the periphery of awareness. Distraction does not make the pain go away, nor does the effectiveness of the use of distraction indicate the absence of pain. Music and humor are extremely effective means of distraction.

Transcutaneous Electrical Nerve Stimulation (TENS) provides low voltage electricity to the body via electrodes placed on the skin. TENS may help with acute or chronic pain. The electrical stimulation of sensory nerves helps block pain signals going to the brain.

Biofeedback is a technique to harness the mind’s power to allow the patient to be more aware of the sensations in the body. The exact mechanism is unclear, but it promotes relaxation and helps reduce pain.

Acupuncture is a neurostimulation technique that treats pain by inserting small, solid needles into the skin at varying depths. Various theories exist to explain how acupuncture works.

Music therapy may be used to treat pain. Music therapy is the clinical and evidence-based use of music interventions to accomplish individualized goals within a therapeutic relationship by a credentialed professional. This individual must complete an approved music therapy program. Research in music therapy supports its effectiveness in various healthcare and educational settings.

Music therapists use music to facilitate changes that are non-musical. Studies done with arthritic patients demonstrated that music helps relieve chronic pain and reduce stress providing positive changes in both mood and emotional state (Garza-Villarreal et al., 2017). Individuals doing music therapy listen to music created under the guidance of a specially educated and certified professional in music therapy.

It is believed that music, like relaxation and guided imagery, can strengthen the right side of the brain, which controls the body's healing processes. The theory of music therapy's effect on chronic pain deals with how pain signals travel through the body. When the brain senses injury to the body, pain signals begin in the somatosensory cortex and the hypothalamus and work their way through the “pain pathway,” ultimately sending pain relief signals. Some signals stimulate the release of neurotransmitters such as endorphins, dynorphins, and enkephalins. Music helps in pain reduction by activating these sensory pathways.

Different surgical interventions or procedures can be used in the pain management plan. Procedures may include injections, spinal cord stimulation, deep brain stimulation, neural ablative techniques, and surgical interventions. These are potential options for those for whom other methods have not controlled the pain.

Pharmacologic Interventions

Analgesic agents are often given orally as this is convenient and allows a relatively steady blood concentration of the drug. Pain medication may be administered on an as-needed basis for episodic pain or given routinely for chronic pain. The use of routine, around-the-clock medication sustains a steady state in the blood and offers better pain relief for those with persistent pain.

Classes of medications include non-opioid analgesic agents, antidepressants, muscle relaxants, antiepileptic medications, topical agents, and opioids. Some get effective relief from one medication, but some get better pain relief from a combination of medications that work on different pathways. Unfortunately, research is sparse on combination medication in the management of pain.

Considering all co-morbidities is an important step in the management of pain. For example, when a patient is afflicted with chronic pain and depression, some medications may help effectively manage both conditions (for example, duloxetine is approved to treat chronic musculoskeletal pain, including discomfort from osteoarthritis and chronic lower back pain to depression). It is also important to establish the pathophysiology of the pain syndrome, evaluate the medication list, and consider the medication's side effects.

The clinician should distinguish between neuropathic pain and nociceptive pain. The etiology of neuropathic pain must be established, and if the etiology is reversible, manage the underlying problem. For example, if a medication (e. g., metronidazole, nitrofurantoin, isoniazid, or many cancer agents) is the etiology of the neuropathy – if possible, stop that medication.

Medications for neuropathic pain include calcium channel alpha 2-delta ligands (gabapentin and pregabalin), tricyclic antidepressants, serotonin-norepinephrine uptake inhibitors (SNRIs), the lidocaine patch, and narcotic analgesics.

Nociceptive pain is typically treated with non-narcotic and opioid analgesia. Common causes of nociceptive pain include arthritis and chronic low back pain. Acetaminophen is often used as a first-line agent in the management of nociceptive pain. Doses can be hepatotoxic at doses greater than three to four grams daily. Hepatotoxicity may occur even at therapeutic doses of acetaminophen, particularly in those who chronically use alcohol (Yoon et al., 2016).

Non-steroidal anti-inflammatory agents (NSAIDs), which are more effective than acetaminophen, are used as alternatives to acetaminophen and are indicated for mild to moderate pain. In contrast, some are indicated for severe pain. Like acetaminophen, they act synergistically with opioids.

Acetaminophen is not an anti-inflammatory agent but a common over-the-counter medication used in pain management. In the past, it was recommended as a primary agent in managing hip and knee osteoarthritis. Recently it was found in many trials to be slightly better than placebo with minimal clinically important differences (Leopoldino et al., 2019).

Acetaminophen is dosed 325 to 650 mg every four hours or 500-1000 mg every 6 hours, not exceeding 3000 to 3250 mg daily. In the pediatric population, acetaminophen is dosed at 10-15 mg/kg/dose every 4-6 hours with a maximum of 75 mg/kg/day, but no more than 3000-4000 mg a day. The dose should be reduced in those with hepatic insufficiency or alcohol abuse. Absolute contraindication to acetaminophen is liver failure, while relative contraindications include chronic alcohol abuse or hepatic insufficiency. Those on a statin cholesterol medication may need a lower dose of acetaminophen.

Even though acetaminophen is better than a placebo for relieving osteoarthritic pain, nonsteroidal anti-inflammatory drugs (NSAIDs) are more effective than acetaminophen. NSAIDs are recommended as the first line of treatment for moderate-to-severe osteoarthritis (Sofat et al., 2014).

NSAIDs are considered an alternative to acetaminophen for mild to moderate osteoarthritis or chronic low back pain. Compared to acetaminophen, NSAIDs are considered more effective in relieving hip and knee pain in osteoarthritis34 because they act as an anti-inflammatory agent. They are often used for arthritis, strains, sprains, bursitis, and tendonitis. NSAIDs are associated with more side effects and are potentially more problematic, especially in older adults. In older adults, the American Geriatric Society guidelines recommend that persistent pain due to osteoarthritis not be primarily managed with non-steroidal anti-inflammatory agents (Ali et al., 2018). Topical NSAIDs are a good option for those with localized pain.

Oral cyclooxygenase-2 (COX-2) inhibitors, celecoxib (Celebrex) is the main agent on the market in this class, have equal effectiveness when compared to non-selective NSAIDs, but are associated with fewer gastrointestinal side effects. Most NSAIDs are equally effective, but if one agent is ineffective, it may be reasonable to try a different NSAID as there is an individual variation response to different medications (see table below) (Solomon et al., 2020).

Absolute contraindications to NSAIDs include an active peptic ulcer, chronic kidney disease, or heart failure. Relative contraindications include a history of peptic ulcer disease, Helicobacter pylori infection, hypertension, or concomitant use of selective serotonin receptor inhibitors or corticosteroids.

Side effects of NSAIDs include gastrointestinal bleeding, renal insults, adverse cardiovascular effects, headaches, constipation, and mental status changes. Gastrointestinal effects may include gastric ulceration and dyspepsia. Taking the medication with food or antacids may reduce the risk of dyspepsia. Those at high risk of gastric ulceration – older age, on corticosteroids, bleeding problems, or a history of gastric ulceration – should likely not use NSAIDs. The use of a proton pump inhibitor reduces the risk of gastric ulceration with the use of NSAIDs. NSAIDs have the potential to interact with many antihypertensive medications, aspirin, selective serotonin reuptake inhibitors, corticosteroids, and warfarin.

The use of misoprostol or proton pump inhibitors may be considered with NSAIDs to reduce the risk of gastrointestinal ulceration. It may be reasonable to use a COX-2 inhibitor in those at high risk for gastrointestinal bleeding. A COX-2 agent, along with a proton pump inhibitor, can be considered in very high-risk patients. It is also important to check for and eradicate Helicobacter pylori in those when it is present to reduce the risk of NSAID-induced gastrointestinal injury.

NSAIDs have the potential to cause nephrotoxicity. NSAIDs inhibit prostaglandin synthesis, which leads to vasoconstriction of the afferent arteriole in the kidney. This constriction results in a reduction in the glomerular filtration rate. NSAIDs should be used cautiously in those with renal impairment.

NSAIDs have the potential to lead to cardiovascular complications. The use of NSAIDs interferes with the cardioprotective effect of aspirin, raises blood pressure, and may exacerbate heart failure. NSAIDs also may increase the risk of clotting and should be used cautiously in those with a history of venous thrombosis. For those with high cardiovascular risk, NSAIDs should be limited.

NSAIDs may interfere with the antiplatelet activity of aspirin therapy (Ruzov et al., 2016). Chronic NSAID use should be avoided in those on chronic aspirin therapy. They should also be avoided in those with thrombocytopenia (low platelet count). Patients receiving warfarin or heparin should not receive NSAIDs.

Examples of Non-Steroidal Anti-inflammatory Agents
  • Choline magnesium trisalicylate (Tricosal®, Trilisate®) is dosed 500-1000 mg every eight to twelve hours.
  • Celecoxib (Celebrex®) is dosed 100 - 200 mg daily.
  • Ibuprofen is maximally dosed at 2400 mg daily divided every 6 to 8 hours. The use of 200-400 mg every six to eight hours is often used.
  • Naproxen is maximally dosed in 1000 mg a day, divided every 8 to 12 hours. An often-used starting dose is 250 mg twice a day.

Antidepressant Use in Pain Management

Antidepressant medications are effective for multiple types of chronic pain. They have shown effectiveness in neuropathic pain, fibromyalgia, and pain associated with depression. This next section will look at some of the antidepressants used to manage pain.

Tricyclic antidepressants (TCA) modify pain by inhibiting the uptake of norepinephrine and serotonin and block multiple channels, including the sodium, adrenergic, cholinergic, and histaminergic channels. Medications in this class include nortriptyline, desipramine, amitriptyline, and imipramine.

Nortriptyline and desipramine (secondary amine tricyclic antidepressants) are preferred in this class as they are associated with a better side effect profile. These agents are often used in the management of neuropathic pain but can also be used in chronic pain management as adjuvant agents.

To achieve moderate pain relief in neuropathic pain, the number needed to treat one patient to see benefit ranges between 2 and 3 (Rosenquist, 2019).

Tricyclic antidepressants need to be used cautiously in older adults as they have many side effects (constipation, dry mouth, mental status changes, blurred vision, urinary retention, blood pressure change, tachycardia, and heart block). They should be used cautiously or not in those with cardiac or electrocardiographic abnormalities. The analgesic effect is typically noticed in a shorter period and at a lower dose than when treating depression. Some patients will have diminishing side effects as their body adapts to the medications.

In adults, most TCAs are often started at 10 mg per day and are then titrated up to 75 mg per day. Older individuals rarely tolerate more than 75-100 mg daily doses. It may take up to 8 weeks before analgesia is appreciated, but pain relief may be noticed as soon as one week.

Serotonin-norepinephrine reuptake inhibitors are used for neuropathic pain but can be used for other types of pain. Duloxetine (Cymbalta) is indicated for diabetic neuropathy and painful chronic musculoskeletal conditions such as osteoarthritis and low back pain. It is also approved for fibromyalgia. Common side effects include insomnia, drowsiness, dry mouth, fatigue, nausea, and dizziness.

Duloxetine should be started at 20-30 mg daily for at least a week before increasing to 60 mg daily. It should not be used in those with severe renal insufficiency or hepatic insufficiency. When stopped, it should be tapered slowly due to potential withdrawal symptoms.

Venlafaxine (Effexor), another SNRI, is sometimes used for neuropathic pain but is an unlabeled use. It is dosed between 75-225 mg per day, and it may take 1-2 weeks for relief to be noticed and may take up to 6 weeks for full benefit. Venlafaxine may lead to increased blood pressure. When the medications stop, they should be tapered slowly to minimize withdrawal symptoms.

For serotonin-noradrenaline reuptake inhibitors to result in pain relief for neuropathic pain, the number needed to treat one patient to see the benefit is between 4.5 and 6.4 (Finnerup et al., 2015). Most of the benefit was noticed with duloxetine, and other researchers have suggested that there is minimal evidence to support venlafaxine for use in neuropathic pain (Gallagher et al., 2015).

Anti-epileptic Agents

Gabapentin is approved in adults for postherpetic neuralgia up to 3600 mg per day in divided doses. Dosage adjustment is needed in those with renal disease. It comes in an extended-release form called Gralise. Gabapentin is often used off-label for other neuropathic conditions, including diabetic neuropathy, generalized neuropathic pain, anxiety, and post-operative pain.

Pregabalin (Lyrica) can be used in adults for fibromyalgia, neuropathic pain (diabetes-related), neuropathic pain in those with spinal cord injury, and postherpetic neuralgia. It is started at 75-150 mg per day in divided doses. The typical effective dose is 300 mg per day in divided doses, with a maximum dose is 600 mg per day. A dose adjustment is needed in those with a creatinine clearance of less than 60 mL/min. Pregabalin may interact with some angiotensin-converting enzyme inhibitors.

Carbamazepine has been used and studied in some chronic pain conditions. Most studies done with carbamazepine have been of short duration and looked at conditions like trigeminal neuralgia, post-stroke pain, and diabetic neuropathy. Studies have shown some improvement in pain but have been criticized for being of short duration (less than four weeks), having questionable reporting quality, and having outcomes that did not represent a substantial clinical benefit. Some studies showed adverse effects were much more prevalent and suggested that two in every five patients treated with carbamazepine will experience an adverse event compared to those treated with a placebo.

There is minimal but some evidence to support the effectiveness of oxcarbazepine in painful neuropathic conditions, including diabetic neuropathy, neuropathy of a mixed origin, and radiculopathy. The research that shows the benefit was small and had a bias. Also, significant adverse effects often resulted in stopping oxcarbazepine when compared to placebo (Zhou et al., 2017).

Other Agents

Topical lidocaine is used as first-line therapy for post-herpetic neuralgia. It must be applied to intact skin, and up to three patches may be applied for no more than 12 hours in 24 hours.

Muscle relaxants can be used in the management of acute and chronic pain. Cyclobenzaprine (Flexeril®) was initially classified as a tricyclic antidepressant but remade as a muscle relaxer. Side effects are similar between the TCAs and the cyclobenzaprine, including sedation, dry mouth, constipation, urinary retention, and mental status changes.

Carisoprodol (Soma®) is another commonly used muscle relaxer increasingly linked to dependence. Due to the concerns of dependence, this medication is less commonly used. Older muscle relaxers include metaxalone (Skelaxin®) and orphenadrine (Norflex®). The most common side effect of all muscle relaxers is sedation.

Two medications that are not FDA-approved as muscle relaxers are often used as muscle relaxers. Tizanidine (Zanaflex®) is used to treat spasticity, but there is evidence that it works for acute and chronic pain. Like other medications in this class, it often causes sedation. Lioresal (Baclofen®) is another antispasmodic agent used for musculoskeletal pain.

Opioids

NSAIDs are laced with risks, and some patients are unable to tolerate NSAIDs due to side effects and co-morbid conditions. The risk associated with NSAIDs is one reason many clinicians choose an opioid to manage pain. Opioid therapy is effective in managing many chronic pain conditions, including osteoarthritis, low back pain, neuropathic pain, and postherpetic neuralgia.

In recent times opioid therapy has become more commonly used; in the past, it was only used for severe acute pain and cancer pain. The use of opioids has come under much scrutiny over the last few years due mainly to the increase in opioid-related deaths.

A position paper from the American Academy of Neurology suggested that there is evidence for good short-term pain relief with opioids. Still, no good evidence exists for continuing pain relief or improved function for extended periods without sustaining a serious risk of dependence, overdose, or addiction (Franklin, 2014).

When non-opioid therapy is ineffective or there is severe nociceptive pain, opioid therapy is often used. Opioid therapy is often used to manage neuropathic pain but is commonly thought to be the second line to antidepressants and anticonvulsants.

Side Effects

Opioid medications are associated with multiple side effects, including constipation, nausea, vomiting, pruritus, abdominal cramping, sedation, and mental status changes. Multiple interventions are available to reduce side effects.

  • Constipation is a frequent issue in those who use opioids. Risk factors for constipation include older age, those with intra-abdominal pathology, and those who eat a low fiber diet. Those on opiates should be encouraged to increase fiber intake, drink plenty of fluids, and be encouraged to exercise. Stool softeners (e.g., docusate sodium) and stimulants (e.g., bisacodyl) may be needed to manage constipation. An osmotic laxative such as polyethylene glycol or lactulose may also be considered, which may be added to stool softeners/stimulants for resistant constipation.
  • Antiemetic medication can help treat nausea.
  • Antihistamines can treat pruritus.
  • Opioids are associated with somnolence and other mental status changes. Patients do develop tolerance to these symptoms over weeks. Reducing the dose may lessen the mental status changes. An adjunctive medication may be added to the lower dose of opioids to help manage the pain. Rarely the use of a stimulant can be used to manage sedation due to opioid use.
  • Respiratory depression may occur, but it is uncommon to use the medication carefully. Starting low and slowly titrating the dose will reduce the risk of respiratory depression. Problems arise with rapid titration, the addition of another drug that may suppress the respiratory drive (benzodiazepine, alcohol, or a barbiturate) or the patient overdoses. Sedation precedes respiratory depression, so when starting a patient on opioid therapy, encourage them to take the first dose in the office to be monitored or in the presence of a responsible adult who can help monitor the patient. The level of consciousness should be assessed 30-60 minutes after the opioid is given. The next dose should be held, and the prescriber should be contacted immediately if there is a reduced level of consciousness, hypoxia, or respiratory rate of less than 10 per minute.

Morphine

While there are many opioids, morphine is considered by many as a standard comparator for other drugs. Morphine can be given orally, rectally, intravenously, subcutaneously, or intramuscularly.

Morphine is used for moderate to severe acute pain and chronic severe pain. It comes in multiple formulations. Its oral and rectal formulation is dosed at 5-30 mg every 4 hours for acute pain. It is available as a tablet, suppository, and parenteral solution. Morphine also comes in a controlled release form, a sustained-release form, and an extended-release form.

Longer-acting formulations include:

  • Arymo® ER and MorphaBond® ER are extended-release tablets. The initial dose is 15 mg every 8 to 12 hours in those not opioid-tolerant or as the first opioid used. It can be titrated every 1-2 days.
  • Kadian® is not indicated for initial opioid analgesia. For non-opioid tolerant patients, 10-30 mg daily is recommended. Higher doses are indicted for opioid-tolerant patients. Titration® may be done every 1- 2 days. Converting from other forms of morphine may be given once or twice a day.
  • MS Contin® is started at 15 mg every 8-12 hours, with the dosage adjusted every 1-2 days.

Morphine should not be used in those with a hypersensitivity to morphine, those with toxin-mediated diarrheal disease, and those with severe/acute asthma, paralytic ileus, or severe respiratory depression. The extended-release form should not be used in those with GI obstruction.

The extended-release forms of morphine are not interchangeable. Changing from one medication to another should be done only by those experienced in how to do this. Extreme caution should be used when using a highly concentrated solution so overdoses do not occur.

Side effects of morphine are like other opioid analgesics and include dry mouth, constipation, bradycardia, hypotension, nausea, drowsiness, dizziness, mental status changes, fever, itching, weakness, hypoxia, and urinary retention.

Drug interactions commonly seen with morphine include:

  • Amphetamines may increase the effect of morphine
  • Anticholinergic agents may increase the side effects of morphine (constipation and urinary retention)
  • Antipsychotic agents with morphine may reduce blood pressure
  • Nasal azelastine (Astelin®) with morphine enhances the central nervous system (CNS) depression effect
  • Clopidogrel therapeutic efficacy may be reduced with morphine
  • Diuretics' side effects may be increased with morphine
  • Hydrocodone enhances CNS depression
  • Hydroxyzine enhances CNS depression
  • MAO Inhibitors enhance the side effects of morphine
  • Selective serotonin reuptake inhibitors with morphine enhance the serotonergic effect and CNS depression
  • Zolpidem enhances the CNS depression

Fentanyl

Fentanyl can be given as an injection, transdermal patch (Duragesic®), an oral transmucosal lozenge (Actiq®), a sublingual tablet (Abstral®), a sublingual spray (Subsys®), a buccal tablet (Fentora®), a buccal film (Onsolis®) and a nasal spray (Lazanda®). The transdermal patch is used in opioid-tolerant patients with moderate to severe pain and is often started at 25 mcg per hour and changed every 72 hours.

Fentanyl can be used for multiple reasons, including premedication for surgery, general anesthesia, as an adjunct to general and regional anesthesia, and chronic pain management. The transdermal patch is for around-the-clock pain management in those with severe chronic pain. Fentanyl transmucosal and intranasal is indicated for cancer pain.

While no official dosage adjustment is recommended in those with renal or hepatic impairment, those with mild to moderate renal or hepatic impairment should likely have the dose reduced by 50 percent with the patch, and the use is not recommended in severe renal or hepatic impairment. Transmucosal and nasal spray have no specific recommendations for dose reduction in renal or hepatic impairment.

As with most opioids, contraindications include hypersensitivity, toxin-mediated diarrheal disease, and paralytic ileus. It should not be used for short-term pain or post-operative pain and should not be used for those who have severe respiratory disease. The transmucosal and nasal forms of fentanyl are typically only used by specialists for opioid-tolerant cancer patients.

The patch form should not be exposed to external heat, as this may increase the absorption of the medication. Patients with a fever may also notice an increase in the absorption of the medication. The patch should only be applied to intact skin, contains aluminum and must be removed before an MRI.

Like many medications, there are multiple potential interactions. Some more common interactions include:

  • Alcohol may enhance CNS depression
  • Beta-agonists may decrease the serum concentration of fentanyl
  • Amphetamines may enhance the effects of fentanyl
  • Anticholinergic medications, along with fentanyl, increase the risk of urinary retention and constipation
  • Antipsychotic agents may increase the risk of low blood pressure
  • Azelastine nasal spray may enhance CNS depression
  • Beta-blockers with fentanyl enhance bradycardia
  • Calcium channel blockers may enhance hypotension or bradycardia
  • Hydrocodone may enhance CNS depression
  • Selective serotonin reuptake inhibitors with fentanyl may enhance serotonergic properties
  • Zolpidem effects may be enhanced

Oxycodone

Oxycodone is a schedule II-controlled substance and is available in multiple forms.

  • Immediate release is dosed 5-20 mg every 4-6 hours (lower range for opioid-naive patients).
  • The controlled release tablet is indicated for those requiring around-the-clock pain control. It is dosed 10 mg every 12 hours to start and titrated carefully. There is also an extended-release capsule, starting at 9 mg every 12 hours.
  • It also comes as an oral concentrate and oral solution.
  • Oxycodone is often combined with other analgesic agents such as acetaminophen, aspirin, and ibuprofen.

Those with a creatinine clearance of less than 60 mL/min should have the dose adjusted as serum concentration of oxycodone will increase in renal insufficiency. Those with hepatic impairment should have doses reduced. The starting dose should be lowered one-third to one-half and slowly titrated to effect.

Oxycodone is contraindicated in those with paralytic ileus, significant respiratory depression, hypercarbia, acute or severe bronchial asthma, and GI obstruction.

Caution should be used in those with biliary tract impairment, such as acute pancreatitis, as it may lead to constriction of the sphincter of Oddi. It may lead to an elevation of intracranial pressure (ICP) and should be used carefully for those with intracranial lesions, elevated ICP, or a head injury. Common drug interactions with oxycodone:

  • Alcohol may enhance CNS depression
  • Amphetamines may increase the effect of oxycodone
  • Anticholinergic agents may increase the side effects of oxycodone (constipation and urinary retention)
  • Antipsychotic agents with oxycodone may reduce blood pressure
  • Nasal azelastine (Astelin) enhances CNS depression
  • Diuretics' side effects may be increased with oxycodone
  • Hydrocodone enhances CNS depression
  • Hydroxyzine enhances CNS depression
  • MAO inhibitors enhance the side effects of oxycodone
  • Mirtazapine may enhance CNS depression
  • Rifampin may decrease the serum concentration of oxycodone
  • Selective serotonin reuptake inhibitors with oxycodone enhance the serotonergic effect and CNS depression
  • Zolpidem enhances the CNS depression

Hydrocodone

Hydrocodone, which was classified as a Schedule II Controlled Substance in October of 2014, is available as a combination pill with non-narcotic analgesia and by itself in an extended-release form. The combination pill has a short-acting version of hydrocodone and is dosed with 2.5 to 10 mg of hydrocodone every 4-6 hours as needed for moderate to severe pain.

Hydrocodone extended-release (Zohydro® ER) is typically dosed 10 mg every 12 hours in treatment-naive patients. It is used for severe pain requiring around-the-clock dosing of hydrocodone. The dose may be increased every 3-7 days in 10 mg increments. Hysingla® ER is dosed with 20 mg once a day while increasing the dose of 10-20 mg every three to five days. Vantrela® ER is also available and is initially dosed at 15 mg every 12 hours.

Those with severe hepatic impairment should start at the lowest dose and titrate up slowly while monitoring for side effects. Caution should be used with renal impairment as plasma concentration may rise.

Contraindications to hydrocodone include paralytic ileus, severe asthma, severe respiratory depression, and hypercarbia. Drug interactions include:

  • Alcohol may enhance CNS depression
  • Amphetamines may increase the effect of hydrocodone
  • Anticholinergic agents may increase the side effects of hydrocodone (constipation and urinary retention)
  • Nasal azelastine (Astelin®) enhances the CNS depression
  • Diuretics' side effects may be increased with hydrocodone
  • MAO inhibitors enhance the side effects of hydrocodone
  • Selective serotonin reuptake inhibitors with hydrocodone enhance the serotonergic effect and CNS depression
  • Zolpidem enhances the CNS depression

Tramadol

As of August 18, 2014, the DEA placed tramadol into a Schedule IV of the Controlled Substance Act. It is indicated for chronic moderate-to-severe pain. For those who do not need a rapid onset of pain relief or are affected by side effects, it may be dosed at 25 mg/day and titrated up every three days to 50-100 mg every 4-6 hours to a maximum of 400 mg a day.

Tramadol also comes in an extended-release form, which is dosed 100 mg once a day and may be titrated by 100 mg every five days to a maximum dose of 300 mg daily.

When prescribing tramadol to older adults, use the lower end of the dosage range and titrate slowly. In those over 75 years old, 300 mg a day should not be exceeded and utilize extreme caution with the extended-release form.

In those with a creatinine clearance less than 30 mL/min, only the immediate release formulation should be used with doses of 25-100 mg split every 12 hours (maximum 200 mg a day). In those with severe liver impairment, the immediate release form should be given at 50 mg every 12 hours.

Patients may experience withdrawal symptoms from tramadol, including nausea, diarrhea, anxiety, pain, sweating, tremor, and rigors. Extended use of tramadol may lead to dependence, and these medications should be tapered slowly to reduce the risk of withdrawal symptoms.

Tramadol has been shown to increase the risk of seizures. This risk is increased in those who take serotonin reuptake inhibitors, tricyclic antidepressants, neuroleptics, other opioids, or drugs that lower the seizure threshold. The risk may also be increased in those with seizures or who are at risk for seizures, such as those with a CNS infection, cancer, history of head trauma, or while patients are going through drug or alcohol withdrawal.

Drug interactions include:

  • Alcohol may enhance CNS depression
  • Amphetamines may increase the effect of tramadol
  • Anticholinergic agents may increase the side effects of tramadol (constipation and urinary retention)
  • Antiemetics may reduce the effects of tramadol
  • Antipsychotics and tramadol may result in reduced blood pressure, increased risk of the neuroleptic malignant syndrome and increased risk of serotonin syndrome
  • Nasal azelastine (Astelin®) enhances CNS depression
  • Carbamazepine with tramadol may enhance CNS depression; tramadol may reduce the therapeutic effect of carbamazepine
  • Cyclobenzaprine and tramadol may increase the risk of seizures or increase the risk of serotonin syndrome
  • Diuretics' side effects may be enhanced with tramadol
  • Hydrocodone may enhance CNS depression
  • Hydroxyzine may enhance CNS depression
  • MAO inhibitors with tramadol may increase the risk of seizures or increase the risk of serotonin syndrome
  • Metoclopramide with tramadol may increase the side effects of metoclopramide or increase the risk of serotonin syndrome or neuroleptic malignant syndrome
  • Selective serotonin reuptake inhibitors with tramadol may increase the risk of seizures or increase the risk of serotonin syndrome
  • Tricyclic antidepressants with tramadol may increase the risk of seizures or increase the risk of serotonin syndrome
  • Warfarin with tramadol may affect the anticoagulant effect
  • Zolpidem enhances CNS depression

Case Study 1

Ms. T is a 54-year-old female with a history of bilateral knee osteoarthritis; she currently rates the pain as a 7/10 in her right knee and 5/10 in her left knee. She takes about three times a day of celecoxib 200 mg twice a day and uses 1000 mg of acetaminophen for breakthrough pain. She has been stable with these medications for the past six months, but over the last month, she has not been getting adequate relief from her pain and has been progressively disabled and has stopped exercising because of pain in her knees.

In addition to osteoarthritis, she has a past medical history of hypertension, dyslipidemia, depression, and obesity. She has a past-surgical history of an appendectomy as a child. She is currently on atorvastatin, lisinopril, celecoxib, and acetaminophen. She has no known allergies.

She has no history of alcohol, drug, or substance abuse. She has a strong family network, including a supportive husband of 25 years and two sons who live within twenty miles of her home. She has a history of depression but is currently not depressed.

The physical exam shows significant crepitus in both knees and obesity (BMI of 34). She is unable to extend the right knee due to pain.

An x-ray demonstrates moderate arthritic changes in both knees. The patient is unwilling to consider the surgery on her knees.

The prescriber offers tramadol immediate-release 25 mg in the morning, which is titrated every three days in 25 mg increments as distinct doses to 100 mg/day (25 mg four times a day). Pain control was still inadequate, and the dose increased from 25 mg every three days to 50 mg every 6 hours.

Pain control was significantly improved, and the patient was given tramadol SR 200 mg once a day. The patient was able to function and exercise. Her quality of life was much improved.

Other Medications

Oxymorphone, a schedule II medication, can be given intravenously, subcutaneously, intramuscularly, or orally. For acute pain, the immediate-release tablet (Opana®) is used at 5-20 mg every 4-6 hours as needed for opioid naïve patients. Caution should be used in those with a creatinine clearance of less than 50 mL/minute, and the medication should not be used in moderate to severe hepatic impairment.

Hydromorphone can be given orally, rectally, subcutaneously, intramuscularly, or intravenously. The oral medication comes in standard and extended-release forms. The standard form is used for moderate to severe pain and is often dosed with 2 to 4 mg tablets every 4-6 hours. The oral liquid is typically dosed with 2.5 to 10 mg every 3 to 6 hours. Parental and oral doses are not equivalent. The parenteral dose is five times more potent than the oral dose. The long-acting form (Exalgo®) is used for opioid-tolerant patients with chronic severe pain. It is dosed 8-64 mg once a day.

Methadone can be given intravenously, subcutaneously, intramuscularly, or orally. The oral dose is started in the opioid-naïve patient at 2.5 every 8-12 hours. Methadone is a high-risk drug that leads to overdose. It has a half-life of up to five days and may accumulate in the body. Methadone may also prolong the QT interval leading to cardiac arrhythmias, especially at doses higher than 120 mg daily. Methadone should be used for severe pain that has not been responsive to other agents and only by clinicians with specific training in using methadone. Methadone is also used in detoxification.

Tapentadol (Nucynta®, Nucynta® ER) is used for acute moderate to severe pain and starts at 50-100 mg every six hours for the immediate-release formulation. The starting dose for the extended-release tablet is 50 mg every 12 hours. For chronic pain, it is typically dosed 100-250 mg two times a day as needed. This medication is not recommended for those with severe liver or renal insufficiency. It is also indicated for diabetic peripheral neuropathy.

Propoxyphene has been taken off the US market as it has been linked with fatal cardiac arrhythmias. Meperidine is not recommended as a first-line agent for chronic pain as it is associated with high central nervous system toxicity rates.

Opioid Dosing in Pediatrics

Many narcotics are available in liquid form for pediatric use. Acetaminophen with hydrocodone is available as an elixir. Acetaminophen with oxycodone and oxycodone alone is also available in liquid form. The dose is based on oxycodone and is dosed at 0.05 to 0.15 mg/kg/dose every 4-6 hours to a maximum of 5 mg per dose. Morphine is available as an immediate-release formulation and is dosed at 0.2 to 0.5 mg/kg every 4-6 hours to a maximum of 30 mg per dose. Hydromorphone is dosed at 0.05 mg/kg every 4-6 hours to a maximum of 5 mg per dose.

Schedules of Controlled Substances

In 1970, section 812 of the Controlled Substance Act was enacted, which lists controlled substances (DEA, 2020). The list describes basic or parent chemicals that may be classified as controlled substances. The Controlled Substance Act divides the drugs and other substances into five schedules, which are updated annually here.

Schedule I controlled substances have no accepted medical use in the United States, have a high potential for abuse, and lack safety data. Substances in this class include heroin, marijuana, 3,4-methylenedioxymethamphetamine ("Ecstasy"), and lysergic acid diethylamide (LSD).

Schedule II and IIN substances may potentially be abused and may lead to severe physical or psychological dependence. Schedule II narcotics include oxycodone (OxyContin®, Percocet®), hydrocodone (Vicodin®, Zohydro® ER), fentanyl (Sublimaze®, Duragesic®), methadone (Dolophine®), hydromorphone (Dilaudid®), morphine, opium, and codeine. Schedule IIN stimulants include methylphenidate (Ritalin®) and amphetamine (Dexedrine®, Adderall®).

Schedule III or IIIN substances have less abuse potential than those substances that are Schedule I or II. They are at high risk for psychological dependence and low to moderate risk of physical dependence. Examples of medications in this class include buprenorphine (Suboxone®) and products with less than 90 milligrams of codeine per dosage unit, such as Tylenol® with Codeine. Medications considered Schedule IIIN include: anabolic steroids such as Depo-Testosterone and ketamine.

Schedule IV controlled substances have a lower potential for abuse when compared to Schedule III controlled substances. Examples of medications in this class include benzodiazepines, midazolam (Versed), modafinil (Provigil®), tramadol (Ultram®), and carisoprodol (Soma®).

Schedule V controlled substances have a low abuse potential relative to Schedule IV substances. Examples of medications in this class include cough preparations containing less than 200 milligrams of codeine per 100 milliliters or 100 grams, such as Robitussin®, AC, lacosamide (Vimpat®), and pregabalin (Lyrica®).

The Controlled Substance Act regulates five medications: anabolic steroids, depressants, hallucinogens, narcotics, and stimulants. Each class has different properties, and substances in each class typically produce similar effects. Most controlled substances alter mood, feeling, or thought due to their effect on the central nervous system. Medications that produce euphoria are more likely to be abused, but medications may be abused to aid in sleep, reduce pain, reduce anxiety, reduce depression, and improve energy.

When opioid therapy is prescribed, it is important to record the discussion between the patient and the provider. The documentation must include the diagnosis being treated and the medication that will be used to manage the diagnosis. Also, the goals of therapy, along with the anticipative results, should be documented. Any alternative or additional therapies should be discussed. When discussing the medications, it is important to document significant adverse reactions, the risk for addiction or withdrawal, and medication interactions.

Prevention of Misuse

To prevent prescription drug abuse, the clinician needs to ensure:

  • Patients are assessed and reassessed
  • Treatment agreements are used
  • Prescription monitoring occurs
  • Safe prescription methods are practiced

The patient's risk should be assessed, and contraindications should be immediately identified. Absolute contraindications to opioids include acute diversion, previous use of opioids that were discontinued from side effects, intolerance or ineffectiveness despite adequate dosing, uncontrolled suicide risk, psychiatric instability, severe respiratory instability, diagnosed non-nicotine substance use disorder, or use of a medication that can produce life-limiting drug-drug interactions (ICSI., 2017).

When taking a patient history document, the opioid currently prescribed, its dose, frequency, and duration of use. It is important to query the state prescription drug monitoring program (PDMP) to confirm the patient’s report of prescription use. Also, it is important to contact past providers to obtain medical records.

Before controlled substances are prescribed, history of illegal substance use, alcohol use, tobacco use, prescription drugs use, family history of substance abuse and psychiatric disorders, history of sexual abuse, legal history, behavioral problems, employment history, marital history, social network, and cultural background should be assessed. History of substance abuse does not prohibit treatment with opioids but may necessitate more intensive monitoring or referral to an addiction specialist.

Multiple tools are available to evaluate opioid risk. The Opioid Risk Tool is a tool that is used in primary care to screen adults for the risk of aberrant behaviors when they are prescribed opioids for chronic pain. It is a copyrighted tool, encompasses five questions, and takes about one minute to use. It classifies a patient as having a low, moderate, or high risk of abusing opioids. Those who are high risk have a high likelihood of aberrant drug-related behavior. It is not validated in individuals without pain. The five questions include family and personal history of substance abuse (alcohol, prescription drugs or illegal drugs), age (risk is 16-45 years old), psychological disease, and history of preadolescence sexual abuse. The questions are scored with different points assigned for each question, which is variable between men and women, and the total score is tallied. The patient is placed at low, moderate, or high risk.

Regular follow-up is important and should occur a minimum of every three months. When assessing the pain patient, the five A’s should be assessed: analgesia, addiction, activities of daily living, adherence, and adverse effects. Part of the follow-up should be urine drug testing, which can be used to detect medication adherence and illicit and non-prescription drug use. It is critical that the clinician adequately document any interactions with patients, assessments, results of testing, and treatment plans.

Written treatment agreements, which should be used between prescribers and patients when controlled substances are used, help guide the conversation between patient and prescriber. It discusses expectations, the risks, and the monitoring that will occur to limit the complications of controlled substances (See table below).

Points Commonly Seen in Opioid Agreements
  • Early refills will generally not be given
  • Patient will not seek controlled substances from another provider
  • Patient will use only one pharmacy
  • Permission for the prescriber to speak freely with other health care providers, pharmacists, and family members regarding opioid use
  • Patient will submit to urine drug test
  • The patient will safeguard the medications
  • Common side effects of the medication will be discussed

Prescription monitoring programs are available in most states, including Oregon. They provide an online database that lists all prescriptions of controlled substances dispensed to each patient by pharmacies. Ideally, the prescriber should check the database before prescribing controlled substances. A patient with an undisclosed prescription for controlled substances is prescription drug misuse.

When abuse/misuse is detected, how should the clinician respond? If it is a minor deviation, counseling and more intensive monitoring may be all that is needed. Tapering controlled substances to reduce the risk of withdrawal is appropriate in more severe or persistent cases of misuse. When diversion is the cause of misuse, immediate prescription removal is likely the best course. A referral to an addiction specialist is recommended if a substance abuse disorder is suspected.

Pain in Special Populations

Pediatrics

Neonates feel pain like any other patient. Untreated or not treated appropriately may lead to long-term effects, including altered sensitivity to pain (Kanwaljeet et al., 2019).

It is important to have a standard method to assess pain in neonates. It is difficult to assess pain in neonates and infants because they cannot communicate. In this population, assessment is based on physiological and behavioral factors. Factors that suggest pain in neonates and infants include vital signs, oxygen saturation, skin color, crying pattern, facial expressions, muscle tone, and consolability. Scales for pain in neonates in the neonatal intensive care unit include Neonatal Facial Coding System, Neonatal Infant Pain Scale, and the Neonatal Pain Agitation and Sedation Scale. No tools are universally accepted to assess pain in infants and children. In neonates, pain assessment tools have difficulty detecting pain in those with very low birth weight, on paralytic medications, or those with prolonged pain.

Due to the difficulty in finding and quantifying pain in neonates and young children, pain management should include an attempt to reduce or prevent pain in the face of potentially painful situations. Limiting the number of painful procedures performed on young children is important.

Pain in children is like adults. The source of the pain, along with its location and severity, should be ascertained. In older children, self-reporting is a reasonable technique to assess pain. For those too young to understand self-reporting, scales such as the facial expression scale can be used. With the help of a caregiver, observing the child for verbal, motor, or facial expressions will help the clinician determine the degree of pain in a non-verbal child.

Pain management in children should work to control, lower, or prevent the pain. Pain management techniques are based on the pain's severity, type, duration, and source. Non-pharmacological measures to control pain include physical/occupational therapy and cognitive/behavioral therapy.

Pharmacological agents may also be considered. Mild pain can be managed with NSAIDs or acetaminophen when pain is not responsive to these medications. The use of stronger medications, including opioids, is considered. Regular assessment of pain control during treatment will help ensure proper pain management. Providing pain medication around the clock is a reasonable option when pain is moderate to severe.

Adjunctive therapy, including medications, can be used in children to manage co-morbid depression and anxiety. The use of anticonvulsants for neuropathic pain may also be considered

Older Adults

Age does not cause pain, but many conditions that cause pain are more common in older adults. Older adults are generally undertreated regarding their pain partly because they have problems communicating pain (Feldt et al., 1998). Those with reduced vision, reduced hearing, or impairments in cognition present a bigger challenge in assessing pain.

In cognitively intact individuals, self-reporting pain is the most reliable assessment method. For those with cognitive impairment, simple questions and basic screening tools can often reliably identify pain. Long-term care residents are often afflicted with some degree of cognitive impairment. Residents of long-term care facilities may present with behavioral or physical changes such as pain presentation.

Older adults may not report pain as readily as younger adults. Some older adults believe that pain is part of aging and do not bother to discuss it with the health care team. When assessing older adults, it is important to determine their pain perception. Some patients perceive severe pain as a sign of a serious illness or loss of independence, or they may believe this is just a consequence of aging.

When evaluating an older adult, it is important to have an accurate medication history, including herbal medicines and dietary supplements. Patients should also be asked about alcohol, drug, and tobacco use.

It is also important to determine the patient’s coping techniques. This determination will help the nurse understand how the patient functions and help them deal with the pain most effectively. Many older adults use prayer and hope to assist in coping with pain.

Goals should be set for the patient to determine an acceptable level of pain to allow the patient to have a satisfactory quality of life. Closely monitoring for adverse drug reactions is an important part of managing chronic pain, as many medications have many side effects. A balance should be sought between the quality of life and the side effects/risks of the treatment.

Older adults have some physiological changes that affect the way medications are used. There is a slowing of the gastrointestinal transit time, which may extend the effects of continuous release medications. Changes in gastric pH may affect the absorption of some medications. Chronic liver changes may lead to changes in drug metabolism. Chronic renal insufficiency is common in older adults and may lead to reduced clearance of medications.

Nonverbal Patients

Since pain is a subjective experience, we measure its existence and intensity by the patient’s self-report. Unfortunately, adult patients with cognitive/expressive deficits or who are intubated, sedated, or unconscious may not be able to provide a self-report. Individuals who cannot communicate their pain remain a challenge and are at even greater risk for inadequate pain control.

When patients cannot self-report, other measures must be used to detect pain. Even if they cannot speak for themselves, these patients have the right to pain assessment and management. Valid and reliable methods to assess pain in nonverbal patients are needed. The American Society for Pain Management recommends the following multifaceted approach for detecting pain in this population.

  • Use the Hierarchy of Importance of Measures of Pain Intensity for Nonverbal Patients:
    • Self-report of pain is the most reliable way to assess pain.
      • Although self-report may be possible with mild to moderate cognitive impairment, as dementia progresses, the ability to self-report decreases and eventually becomes impossible. However, even if patients cannot communicate the experience of pain, they still experience pain sensation.
      • Obtaining a report of pain from a critically ill patient may be hampered by such conditions as delirium, decreased level of consciousness, presence of an endotracheal tube, sedatives, and neuromuscular blocking agents, for example. In these situations, the patient’s ability to self-report may wax and wane; therefore, a serial assessment for the ability to self-report should be conducted.
    • Search for Potential Causes of Pain.
      • Assume pain is present and intervene with common problems or procedures known to cause pain (e.g., surgery, wound care, positioning), even without behavioral indicators of pain.
      • Rule out or treat other problems that may cause discomfort (e.g., infection, constipation, urinary retention).
      • Consider chronic pain causes that may have been present before (e.g., history of arthritis or low back pain).
    • Observe patient behaviors – a valid approach only when self-report is absent. The American Geriatrics Society identifies the following six main types of pain behaviors:
      • Facial expressions (grimacing, e.g.)
      • Verbalizations or vocalizations (moaning, e.g.)
      • Body movements like tense body posture
      • Changes in interpersonal interactions (aggression or resisting care, e.g.)
      • Changes in activity patterns (refusing food or increased wandering, e.g.)
      • Mental status changes like crying or increased confusion (Chang & Johnson, 2018).
    • Encourage proxy pain rating by family members or caregivers who know the patient when patients cannot provide self-reports of pain. Inquire about behaviors that may indicate pain or whether preexisting conditions that may cause pain, such as arthritis, are present.
    • Attempt an analgesic trial with procedures or conditions likely to cause pain or when pain behaviors continue after attention to basic needs and comfort measures. Make appropriate adjustments such as increases in dose or addition of other analgesics if behaviors indicative of pain persists or additional potentially painful procedures occur.
  • Establish a Procedure for Pain Assessment.
    • When patients cannot self-report pain, other, less reliable measures must be used to identify its existence. These assessment measures (described above) form a hierarchy of probable importance. Healthcare facilities should institute a procedure for using this hierarchy of assessment techniques as a template for the initial assessment and treatment procedure.
  • Use Behavioral Pain Assessment Tools as Appropriate.
    • The number of studies addressing pain assessment in nonverbal adults who cannot provide a self-report has recently increased. Further study is required to demonstrate their reliability, validity, and usefulness in the clinical setting. When utilizing behavioral pain assessment tools, one must keep in mind the following considerations:
      • Scores obtained when utilizing behavioral pain assessment tools are NOT equivalent to self-reported intensity ratings and should never be documented. Only self-reported intensity ratings may be documented as the “5th Vital Sign”.
      • Pain behaviors may not indicate pain, but another source of distress, such as emotional distress.
      • It is best to observe a patient during care activities when pain behavior is more likely, rather than at rest.
      • Behavioral assessment tools may help identify the presence of pain. They also can be used to evaluate attempts to relieve pain by observing for a decrease in pain behaviors following an intervention.
        • At least 14 behavioral assessment tools have been developed to assess pain in nonverbal patients with dementia. These tools are in varying stages of development and validation. When selecting a tool, choose one that has been researched for reliability and validity in a similar clinical setting. Behavioral assessment tools for the cognitively impaired are of two types: pain behavior scales and pain behavior checklists.
      • Pain behavior scales are scored by identifying the degree of observed behavior. This score is not the same as a pain intensity score. An example of a pain behavior scale is the Pain Assessment in Advanced Dementia Scale (PAINAD). It evaluates and scores five categories of behavior: breathing, negative vocalization, facial expression, body language, and consolability. Each category may receive a score ranging from 0 to 2. Any positive score may indicate that pain is present, and the score can be used to evaluate the intervention but cannot be interpreted to mean pain intensity. For a pain behavior scale to be used, the patient needs to be able to respond in all categories of behavior. For example, the PAINAD should not be used with a patient with quadriplegia since body language could not be scored.
      • Behavior checklists differ from pain behavior scales. They do not evaluate the degree of observed behavior, just its presence or absence, and do not require a patient to demonstrate all the specified behaviors. An example of a pain behavior checklist is the Pain Assessment Checklist for Seniors with Limited Ability to Communicate (PACSLAC). This checklist evaluates 60 behaviors such as restlessness, agitation, decreased activity, and appetite changes—the total number of behaviors that a pain exhibits cannot be equated with a pain intensity score. A patient who scores 5 out of 60 behaviors does not necessarily have less pain than a patient who scores 10 out of 60. In an individual patient, though, a change in the total number of behaviors may suggest more or less pain and can be used to evaluate response to interventions.
        • Tools developed to assess pain with mechanically ventilated or unconscious patients are fewer in number. One such tool – the Adult Nonverbal Pain Scale (NVPS) – was patterned after the Faces, Legs, Activity, Cry, Consolability Observation Tool (FLACC) used to assess pain in infants and children. When tools are adapted and used in different settings, they must be tested for reliability and validity in the new patient population. The NVPS was tested in the Strong Memorial Hospital, Rochester, New York, burn trauma unit. After initial testing, a further revision was made to include a respiratory component with ventilator compliance. This revised scale, which scores the categories of facial expression, activity, guarding, physiology (vital signs), and compliance with ventilator, is currently being implemented in several healthcare institutions while undergoing further testing.
      • Minimize Emphasis on Physiologic Indicators.
        • Research does not support the use of vital sign changes for identifying pain. The absence of an increase in blood pressure, respiratory rate, or heart rate does not indicate an absence of pain.
      • Reassess and Document.
        • Just as with patients who self-report pain, reassessment of pain with non-verbal patients must occur after the intervention and regularly over time. Reassessment should occur utilizing the same initial behavioral pain assessment tool and observing for changes in those behaviors with effective treatment.

Pain in Pregnancy and Labor

Pregnancy is associated with many changes that have the potential to cause pain, such as changing body shape, increasing weight, hormonal shifts, and joint laxity. Acetaminophen is thought to be a safe option for pain control throughout pregnancy. NSAIDs should not be used in late pregnancy. NSAIDs can potentially lead to premature closing of the ductus arteriosus if used in the third trimester.

Many different pain syndromes are commonly seen in pregnancy. Mechanical back pain due to weight distribution changes is one of the most common types. Pain in the pubic symphysis is common and can be managed with position changes and pelvic support devices. Leg cramps may be prevented and treated with calf stretching. Carpal tunnel syndrome is often seen during pregnancy and is likely related to fluid retention, which causes compression of the nerves in the carpal tunnel. Symptoms of carpal tunnel syndrome most commonly occur in the third trimester and resolve after pregnancy but may be prolonged by breastfeeding.

Labor is a painful period, and treatment may involve various techniques. The most reliable pain management method is epidural and spinal analgesic techniques. The use of opioids induces sedation and thereby contributes to pain control. Unfortunately, opioids act systemically, and some effects may be transferred to the fetus leading to respiratory depression in the neonate.

Pain in the Psychiatric Patient

Psychiatric disorders are up to three times higher in those with chronic pain compared to the general population. Depression, anxiety, and post-traumatic stress disorder are the most prevalent psychiatric disorders in patients with chronic pain (Barry et al., 2016). Patients with pain and psychiatric disease typically report more intense pain than those without co-morbid mental illness.

Chronic pain management has multiple challenges in psychiatric patients. Optimizing treatment of the underlying psychiatric illness is an important step to achieving an optimal reduction in pain. It is also important to screen and treat for any substance abuse or substance-induced disorder. This screening will help ensure appropriate and adequate treatment of pain. Medications with abuse potential should be used cautiously, as there is a high prevalence of drug use disorders in psychiatric patients. The use of exercise and cognitive behavioral therapy is an important step in managing pain in psychiatric patients. Also, monitoring for compliance is an important part of managing the psychiatric patient who suffers from chronic pain.

U.S. Centers for Disease Control and Prevention Guideline for Prescribing Opioids

The Center for Disease Control (CDC) and Prevention developed guidelines for prescribing opioids for chronic pain. It offers guidance to the clinician regarding the safe and effective prescribing of opioids and assistance in managing chronic pain. This guideline focuses on patients over 18 who are seen in the primary care setting. The guideline focuses on chronic pain that does not involve end-of-life care, active cancer treatment, or palliative care.

This guideline is meant to help primary care clinicians deal with the 11 percent of adult patients that deal with daily pain (Dowell et al., 2016). It was developed partly because primary care clinicians reported insufficient training in opioid prescribing and concern regarding addiction.

The guideline focuses on three main areas:

  1. Determining when to start/continue opioids for chronic pain includes looking at treatment goals, discussing the benefits/risks of therapy, and the utilization of not only opioid therapy but nonopioid therapy and nonpharmacological therapy
  2. The selection, duration, dosage, follow-up, and discontinuation of opioids
  3. Assessing the risk and addressing the harms of opioid use includes using methods to evaluate and reduce risks. It discusses the use of urine drug testing, the prescription drug monitoring program (PDMP), treatment of opioid use disorder and precautions regarding co-prescriptions of benzodiazepines

Recommendation 1

The first recommendation suggests that chronic pain should be managed primarily with nonpharmacologic and nonopioid pharmacologic therapies. Opioid therapy should be considered only when the risks outweigh the potential benefit in pain control and functional improvement. When opiates are used, they should be combined with nonopioid and nonpharmacological therapy.

Appropriate non-pharmacological therapies include weight loss, physical therapy, exercise, psychological therapies, and selected intervention procedures (joint injections). Nonopioid pharmacotherapy may include NSAIDs, acetaminophen, cyclo-oxygenase (COX)-2 Inhibitors, some anticonvulsants, and some antidepressants. The use of nonopioid pharmacotherapy is associated with a significantly reduced overdose risk.

Recommendation 2

The second recommendation suggests that before initiating opioid therapy in chronic pain patients, it is important to establish realistic goals for pain and function. Also, patients should be educated that opioid therapy would be discontinued if the risks are deemed greater than the benefits. Opioid prescriptions are only continued when there is a meaningful improvement in function and pain, and the benefit outweighs the risk to patient safety.

Research suggests that long-term use of opioids is associated with serious risks and that risk is dose-dependent. Research shows weak evidence that opioid therapy beyond six months results in clinically significant pain relief or clinically significant improvements in quality of life. Many patients who use long-term opiate therapy discontinue therapy due to adverse effects or inadequate pain control. Because of these facts, it is hard to predict which patient will have greater benefits than harms when receiving chronic opiate therapy.

When opioid therapy is initiated, the prescriber should determine how effectiveness will be evaluated. Also, treatment goals should be established with the patient before starting therapy. Goals should include relief in both pain and improvement in function. Conditions that lead to progressive functional impairment or injuries such as spinal cord trauma may have a primary goal of pain relief as opposed to improvements in physical function. The social and emotional well-being of patients should also be considered.

Functional goals may include returning to work, attending specific recreational activities, walking around the block, or taking the dog for a walk. Assessing for depression, anxiety, and other psychological conditions is an important aspect of managing the whole patient. Generally, if pain and function are not improved on opioid therapy, tapering or discontinuing should be strongly considered.

A written agreement should also be used that discusses how opioids will be prescribed and monitored and how they will be tapered or discontinued. Situations, where opioids should be tapered or discontinued include when opioids are not needed, side effects become too severe, or treatment goals are not met (Dowell et al., 2016).

Recommendation 3

The third recommendation suggests that providers should discuss the risks and benefits of opioid therapy both before and during treatment. Also, the responsibilities of both the patient and the clinician should be laid out before and during therapy.

Key teaching points:

  • Functionally improvement is the main goal, even if pain still is present.
  • The use of opioids generally does not improve pain and function in the long term, but opioids may reduce pain in the short term.
  • Discuss common side effects include nausea, vomiting, mental status changes, constipation, dry mouth, drowsiness, tolerance, physical and psychologic dependence, and withdrawal symptoms upon ceasing opioids.
  • Discuss potentially fatal respiratory depression, especially with higher doses or when used with other depressants such as benzodiazepines.
  • Chronic opioid use may lead to a lifelong opioid use disorder.
  • Increase fluid intake and fiber to reduce the risk of constipation.
  • Opioids reduce the ability to operate motor vehicles safely.
  • Discuss that the need for the opioid will be periodically reviewed with consideration given to reducing or discontinuing the opioid.
  • Discuss the importance of not sharing prescriptions among family or friends.
  • Discuss safe storage, such as in a locked location.
  • Discuss the safe disposal of controlled substances.
  • Discuss monitoring that will be used, including urine drug testing and the use of the prescription drug monitoring program.
  • Consider discussing the use of naloxone.

Recommendation 4

Recommendation 4 suggests that when starting opiates for chronic pain, immediate-release opioids are recommended over longer-acting medications. Long-acting opioids are associated with a higher risk of overdose when compared to immediate-acting opioids.

The Food and Drug Administration (FDA) reported in 2014 that extended-release or long-acting opioid pain medications should be used only when pain is severe enough to necessitate daily, around-the-clock, long-term opiate treatment when other options are ineffective not tolerated or would not offer adequate pain management. They should not be used on an as-needed basis.

Other key points under this recommendation include:

  • Certain medications are only appropriate for opioid-tolerant patients. An opioid-tolerant patient is someone who has taken 60 mg daily of oral morphine, 30 mg daily of oral oxycodone, or equianalgesic dosages of other opioids for at least one week.
  • There is not enough evidence to determine if taking immediate-release opioids for breakthrough pain when using ER/LA opioids is safe outside palliative care, end-of-life care, and active cancer.
  • Using abuse-deterrent technologies makes it more difficult and less rewarding to manipulate opioids. While they can still be abused, it is more difficult to do so. The abuse-deterrent technology does not prevent unintentional overdose, and the Center for Disease Control document does not make recommendations regarding abuse-deterrent formulations.
  • Methadone has been found to have the highest number of overdose deaths compared to other opioids prescribed for chronic pain. Methadone also has cardiac complications such as QT prolongation and cardiac arrhythmias. Also, methadone has a variable and long half-life, which can be complicated when peak respiratory depression occurs. There is more interindividual variability in the pharmacodynamics of methadone when compared to other opioids. Methadone should only be used by prescribers familiar with the unique pharmacodynamics and willing to monitor patients on it closely.
  • The pharmacodynamics of transdermal fentanyl is also complex. A gradual increase in serum concentration is noted over the first 72 hours. Absorption can be variable based on factors such as external heat.
  • Opioid treatment should not be initiated with ER/LA dosing, and this type of medication should not be used for intermittent use. They should be considered only in those with severe pain who have used intermediate-release opioids daily for at least seven days.

Recommendation 5

Recommendation five suggests that when starting opiates, the lowest effective dosage should be prescribed. Extreme caution should be used when opiates are prescribed. The risks versus benefits should be reevaluated with dosages above 50 morphine milligram equivalents (MME)/day. If dosages above 90 MME/day are used, careful justification should be documented.

The benefits of high-dose opioids are not well established, and higher doses are associated with more harms such as opioid use disorder, overdose, and motor vehicle accidents.

While lower doses of opiates reduce the risk, there is no dose threshold that overdose risk is eliminated. Dosage above 90 MME/day is linked to a high risk of overdose, with lower dosages associated with less risk. According to the CDC document, when dosages are pushed to over 50 MME/day, the risk of overdose increases without improving pain control or functional benefit.

When increasing the dosages of opioids, it should be done in the smallest amount possible to reduce overdose risk. There is no firm evidence on how long to wait before increasing dosages, but waiting for at least five half-lives before increasing the dosage has been recommended. Also, extreme caution should be used in individuals over 65 or those with kidney or liver insufficiency.

When dosages are increased above 50 MME/day, the prescriber should:

  • Assess if the opiate is helping to meet the treatment goals
  • Increase the frequency of follow-ups
  • Consider providing naloxone
  • Provide overdose education

Even patients who have been on high doses for many years should be offered the chance to wean their dosage. The patient should be educated that recent clinical evidence suggests that patients on high doses of opiates are at higher risk for overdose, and the provider should offer the patient an opportunity to wean dosage slowly if indicated.

Recommendation 6

Recommendation 6 suggests that when opioids are used for acute pain, the provider should use the lowest dose of immediate-release opioids and provide a quantity that is no more than the expected duration the patient needs. Three days or less is often enough, and more than seven days is rarely indicated.

Some research suggests that for back pain managed in a primary care setting, the use of opioid medications results in a large reduction in pain until the fourth day of treatment. After that, smaller pain reductions are noted. Opioids should not be prescribed “just in case.”

Recommendation 7

Recommendation 7 suggests that patients using opioids for chronic pain should have the benefits and harms evaluated within one to four weeks of beginning therapy or when there is a dose increase. After that, the benefits and harms should be evaluated at least every three months. If the benefits do not outweigh the harms, the provider should consider tapering opioids to a lower dosage or discontinuing opioids.

Individuals who continue opioid therapy for three months or more are at increased risk of developing opioid use disorder. Therefore, frequent follow-up in the first three months may help reduce the risk of opioid use disorder. Another argument for close follow-up is that risk of overdose is high during the first two weeks of treatment with ER/LA opioid use. The risk is especially high with methadone or fentanyl.

Research suggests that individuals who do not have pain relief from opioids at one month will likely not have pain relief at six months. Therefore, assessment within the first month is important to determine who will likely benefit from opioid therapy. Frequent assessments should reduce the risk of complications of long-term opioid use such as overdose, opioid use disorder, and other injuries.

Certain individuals are at higher risk for opioid use disorder or overdose, and this includes individuals with a history of a substance use disorder, individuals with depression or another mental health condition, patients taking greater than 50 MME/day, those with a history of overdose, and those taking other central nervous system depressant medications. These individuals should be evaluated more frequently. If these individuals are noted to be without benefit from the opiate, strong consideration should be given to reducing the dose or discontinuing the opiate.

When tapering opioids, the dose should be reduced weekly by 10-50%. In individuals with a severe adverse event, such as an overdose, rapid discontinuation of 2-3 weeks could be utilized. Reducing dosages slowly may be appropriate for individuals who have utilized opioids for extended periods. Reducing as slowly as 10% a month may be utilized in individuals who have been taking opioids for years.

A slow reduction in opioid doses reduces the signs of opioid withdrawal such as anxiety, nausea, vomiting, diarrhea, tremor, increased heart rate, insomnia, drug craving, and abdominal pain.

Recommendation 8

Recommendation number 8 suggests that opioid-related harm risk factors should be assessed before and during opioid therapy. Also, clinicians should implement strategies to reduce risk in individuals at high risk. These strategies would include individuals on greater than 50 MME per day, those with a history of an overdose, a history of a substance use disorder, or those on concurrent benzodiazepines.

One strategy to reduce the risk of overdose death includes prescribing naloxone. Naloxone can reverse the opioid when there is severe respiratory depression. Naloxone can potentially bring on acute withdrawal symptoms in patients who are physically dependent on opioids.

Other factors that place patients at high risk for overdose include sleep-related breathing disorders such as sleep apnea or congestive heart failure, pregnancy, mental health issues, renal or liver insufficiency, and those greater than age 65.

Pregnancy puts both mother and fetus at risk. Opiate use in pregnancy increases the risk of poor fetal growth, birth defects, stillbirth, and preterm delivery. It can also lead to neonatal opioid withdrawal. When prescribing opioids for anyone of childbearing age, it is important to discuss the possible consequences of opioids during pregnancy.

Prescribing medication, including opioids, can be challenging in older adults. Some concerns include reduced renal or hepatic function, higher risk of respiratory depression, increased risk of side effects including cognitive impairment, more comorbid medical problems, polypharmacy, higher risk of falls, and constipation.

Extra caution should be utilized in individuals with mental health problems when prescribing opioids. This group of individuals is at higher risk for opioid use disorder and increased risk for drug overdose (especially in those with depression). For individuals with significant psychiatric instability or high suicide risk, opioid therapy should not be initiated. Also, individuals who have been prescribed benzodiazepines should very cautiously be prescribed opiates, if at all.

Individuals being prescribed opioids should be screened for substance use disorder. The patient should be asked about drug and alcohol use. Also, the prescriber should use the prescription drug monitoring program (PDMP) database before prescribing. For individuals with a substance use disorder obtaining outside consultation with a substance use disorder specialist or pain specialist regarding pain management is recommended.

Recommendation 9

Recommendation number 9 suggests that the clinician review the PDMP database to determine previous/current opioid prescriptions and other medications that may interact and place the patient at higher risk for overdose. The clinician should review this data at a minimum every three months, as often as every prescription is written.

Research is limited on the benefits of PDMPs, but evidence suggests that individuals who received opioid prescriptions from multiple prescribers and high doses are at the highest risk for overdose. The PDMP can help detect these situations.

Providers should not dismiss patients from their practice based on data from these databases. Doing so has the potential to have negative health outcomes. This opportunity allows the provider to intervene to reduce the risk of overdose by providing interventions such as education, considering alternative therapies, or prescribing naloxone.

Recommendation 10

Recommendation number 10 suggests that when prescribing opioids for chronic pain, urine drug testing should be used before therapy and at least once a year. This testing will ensure that the patient is taking the prescribed medications and that there are no illicit drugs in the patient’s system.

The use of other controlled substances increases the risk of overdose. Urine drug testing has the potential to identify these patients and reduce risk. Urine drug testing also can determine when patients are not utilizing prescriptions as prescribed, which may point to diversion or side effects that limit compliance.

While urine drug testing should be done before starting opioid therapy, there is disagreement on how frequently testing should be done during long-term therapy. It should be done at least once a year. In high-risk individuals, more frequent testing is likely indicated.

Patients should be educated that the purpose of drug testing is to improve patient safety. Before testing, the provider should ask about the use of other drugs or medications and if there might be any unexpected results. The clinician should be prepared for unanticipated results and have a plan for dealing with them. Unexpected results should be discussed with the patient to determine if there is a logical explanation. If the unexpected results (for example, negative for a prescribed drug or positive for a random drug) are not explained, then confirmatory testing should occur.

Confirmed unexpected results can lead to one of the following outcomes.

  • Modification of the pain management strategy
  • More frequent evaluations
  • Tapering/stopping the opioids. When testing for expected medications is repeatedly negative, then abrupt discontinuation is appropriate (as the patient is not taking the medication)
  • More frequent re-evaluation
  • Giving naloxone
  • Referral for substance use disorder treatment
  • Clinicians should not remove the patient from care due to an unexpected urine drug test. This removal is a safety measure as the patient could withdraw, obtain medication from another source, or even start heroin. It could also be construed as patient abandonment. Lastly, it may miss a chance to get the patient into treatment for substance abuse disorder.

Recommendation 11

Recommendation 11 suggests avoiding prescribing an opioid and benzodiazepine together. This combination reduces respiratory drive and significantly increases the risk of overdose. The recommendation is not an ultimatum to never prescribe these two agents together but should be done rarely and with extreme consideration. For example, a patient who has been on a long-term, low-dose benzodiazepine and develops severe acute pain may be a candidate for low-dose opiate medication.

Other medications that suppress the central nervous system should be avoided in those on opiates. These may include sedatives, hypnotics, muscle relaxants, some antidepressants, and sedating antihistamines.

Recommendation 12

Recommendation number 12 recommends using an evidence-based treatment in those with opioid use disorder, which may include medication-assisted treatment (MAT) with behavioral therapy.

Points discussed under this recommendation include:

  • Opioid dependence is estimated to be present between 3-26 percent of primary care patients on opioids for chronic pain. MAT is effective in preventing relapse in those with opioid use disorder.
  • MAT can be accomplished with buprenorphine or methadone and, in some cases, naltrexone. Naltrexone blocks opioid effects and can be given daily oral therapy or monthly injections.
  • Providers should be aware of community resources available to help patients get treatment for opioid use disorder.
  • MAT in pregnant women with opioid use disorder improves maternal outcomes. Treatment should be with buprenorphine or methadone, not naltrexone.

The CDC guidelines aim to enhance the communication between patients and providers regarding the risks and benefits of opioid treatment in chronic pain. It also looks to reduce the risks of long-term opioid therapy and improvement.

Specific Pain Syndrome

Visceral Pain

Many conditions lead to visceral pain. Visceral pain occurs when there is a stimulation of nociceptors of the organs in the abdomen, pelvis, or chest. Visceral pain is diffuse, hard to pinpoint, and often referred to as a small structure. Visceral structures are aggravated by ischemia, inflammation, and stretch.

Chest pain can occur from many different etiologies. A few life-threatening situations must be considered, including myocardial infarction, pulmonary embolism, aortic dissection, tension pneumothorax, and esophageal rupture. Most chest pain is not life-threatening, and selected causes include chest wall pain (costochondritis, muscle strain), panic attacks, pneumonia, pleurisy, myocarditis, gastroesophageal reflux disease, and pericarditis.

Abdominal pain is a common problem, and most cases are not life-threatening. It is important to rule out serious causes of abdominal pain like chest pain. Serious causes of abdominal pain are suggested by unstable vital signs, high fever, an inability to pass gas or have a bowel movement, vomiting blood, or having dark/tarry stools. Common potentially life-threatening diagnoses include acute bowel obstruction, acute mesenteric ischemia, bowel perforation, ulcer, acute myocardial infarction, and ectopic pregnancy. Other causes of abdominal pain include appendicitis, gall bladder disease, diverticulitis, constipation, kidney stones, lactose intolerance, and inflammatory bowel disease.

Many patients have chronic abdominal pain, and many of these cases are benign – functional dyspepsia or irritable bowel syndrome. If no organic disease is found, that patient should be treated symptomatically. Individuals over 50 are more likely to have a more serious cause of chronic abdominal pain, and functional abdominal pain should be made only after more serious causes have been ruled out.

Pelvic pain is a common problem in women and may represent a urologic, gynecologic, gastrointestinal, musculoskeletal, metabolic, or vascular issue. Acute pelvic pain may be of visceral or somatic origin. A pregnancy test should be done for all women who have the possibility of being pregnant. Other testing to rule out other causes of pelvic pain includes a complete blood count, sedimentation rate, chlamydia/gonorrhea testing, a serum hCG level, and a urinalysis.

Diagnostic testing may include a pelvic ultrasound to rule out a mass or ectopic pregnancy, or laparoscopy can help determine if endometriosis is present. Features that suggest a serious cause of pelvic pain include peritoneal signs, brisk vaginal bleeding, high fever, or unstable vital signs.

There are many potential causes of chronic pelvic pain. Diagnosing and treating chronic pelvic pain can be challenging. Determining the exact cause of the abdominal pain may include the use of extensive laboratory evaluation, imaging modalities, and at times exploratory surgery. For those with chronic pelvic pain, the examination may use a pain map and identify tender areas to see if physical exam tender areas match the pain map. Ideally, the clinician should attempt to treat the underlying cause of pelvic pain. Still, a non-specific treatment may be considered when there is no specific diagnosis.

Sickle Cell Disease

Sickle cell crisis is a vaso-occlusive phenomenon leading to pain associated with blood cell destruction and subsequent anemia. While not the only feature of sickle cell disease, pain is a major component. Acute sickle cell disease pain is secondary to vaso-occlusion and the consequent tissue ischemia and inflammation. Over time, chronic pain may result. Assessment of pain is challenging in sickle cell crisis as there are no objective findings that definitively confirm a crisis or the degree of pain.

An acute painful episode can precipitate multiple events such as stress, infection, weather conditions, dehydration, or alcohol consumption. Pain can affect many body parts, such as the chest, back, extremities, or abdomen. Many times, pain is associated with fever, elevated breathing rate, hypertension, nausea, and vomiting.

Treatment of pain in chronic disease can be challenging to manage. If mild pain is present and the patient is not on chronic opioid therapy, pain management should be started with non-opioid therapy moving to opioids when the pain becomes more severe. Individuals who are on chronic opioids will require additional opioids for breakthrough pain. When treated in the emergency room, intravenous morphine, hydromorphone, or fentanyl can be used. If pain cannot be relieved with two doses, then admitting the patient to the hospital for pain management may be necessary. Many patients with sickle cell disease have chronic pain managed with long-acting opioids (DeBaun & Vichinsky, 2019).

Headache

Headaches are a frequent cause of recurrent pain and one of the most common diagnoses in health care. There are multiple types of headaches, including migraine, tension, and cluster headache. Tension headache is the most common. The health care provider needs to understand red flags that suggest a serious cause of headaches. When a serious cause of headache is suspected, urgent evaluation is necessary and may include the use of brain imaging to rule out an underlying secondary cause. Signs/symptoms that suggest a more serious cause of headache include:

  • New-onset headaches, especially in those over age 50
  • Worst headache of your life
  • A headache with an accompanied neurologic sign or symptom – e.g., confusion, stiff neck, seizure, focal neurologic sign (e.g., one-sided weakness), impaired alertness
  • Headaches that awaken the patient from sleep
  • Fever and stiff neck
  • Pregnancy – may suggest pre-Eclampsia
  • History of cancer
  • History of HIV or immune compromise
  • Headache made worse by cough, exertion, or the Valsalva maneuver
  • History of recent head trauma
  • Illicit drug use
  • Progressive headache

Tension headaches may occur every day and have a variable presentation. Typically, they are described as pressure, tightness, or aching. They may feel like a band around the head and be bifrontal, bitemporal, or generalized. Tension headaches can be intermittent with a variable duration or constant.

Migraine headaches are classically one-sided (but may generalize) and are pounding or throbbing. Patients with migraines often have co-existent nausea/vomiting or photophobia.

Acute migraine can be managed with multiple agents. The use of acetaminophen or NSAIDs may be considered. When simple analgesics are ineffective in managing pain, the use of migraine-specific agents (triptans or dihydroergotamine) may be considered. These agents are available in oral, rectal, and injectable formulations. Many patients prefer oral agents, but for those with severe nausea that accompanies the migraine, a non-oral route is the best option. Prophylactic agents for migraines include propranolol, amitriptyline, topiramate, and valproic acid.

Neuropathic Pain Conditions

Many conditions lead to neuropathic pain, including multiple sclerosis, post-stroke pain, spinal cord injury, traumatic brain injury, syringomyelia, trigeminal neuralgia, peripheral neuropathy, and post-herpetic neuralgia.

Multiple sclerosis (MS) is commonly associated with pain. It is estimated that 43 percent of MS patients have at least one painful symptom (Olek, 2019). Common painful symptoms include dysesthetic pain, back pain, spasms, Lhermitte sign, visceral pain, and trigeminal neuralgia.

Central post-stroke pain is experienced as unilateral head/facial pain that starts within six months of a stroke. It affects up to 8 percent of stroke victims (Garza, 2019). The pain is typically persistent but may come and go. The severity of the pain may be variable, and stress often exacerbates the pain. Treatment of central post-stroke pain include benzodiazepines, anticonvulsants such as gabapentin; pregabalin; lamotrigine, or carbamazepine; baclofen; antidepressants such as amitriptyline or a SSRIs; and clonidine. When pain is resistant to pharmacotherapy, neuromodulation (deep brain stimulation) and surgery may be considered.

Spinal cord injury (SCI) patients often develop chronic pain after spinal cord injury that affects their quality of life. Pain is often poorly localized and neuropathic (e.g., burning, stabbing). The pain can be evoked or spontaneous. Pain can be at-level pain (pain at the SCI level) caused by injury to the nerve roots and dorsal gray matter, causing pain at the level of the injury. Pain can also be below the level of the SCI, which is thought to be caused by injury to the spinothalamic tracts or thalamic deafferentation. Pain may be managed with antidepressants (e.g., tricyclic antidepressants), antiepileptics (e.g., gabapentin, lamotrigine, or valproate), and standard analgesic medications (opiates). When medications are not effective, the use of invasive treatments is considered. These may include deep brain stimulation, cordotomy, or motor cortex stimulation.

Syringomyelia is a delayed progressive intramedullary cystic degeneration that affects a small number of patients after spinal cord injury. It is thought to occur from scaring and subsequent obstruction of cerebral spinal fluid flow and altered tissue compliance leading to an extension of the central canal, which presses on the nearby cord tissue (Abrams & Wakasa, 2019). In syringomyelia, the patient will present progressive pain that may include sensory, motor, or bowel problems. Treatment of the condition is mainly surgical.

Post-concussion syndrome can occur days or weeks after a traumatic brain injury (TBI). This syndrome can occur with any degree of head injury, from mild to severe. It is characterized by dizziness, vertigo, headache, reduced concentration, apathy, depression, sleep disturbance, confusion, irritability, and anxiety. Headache after TBI typically occurs within seven days of the injury and is typical of the tension-type or migraine-type headache. In those with TBI, many other headache syndromes may be seen. While post-concussive syndrome is often reported in athletes, it is more common in older adults. MRIs may be performed for patients with symptoms that persist in ruling out other problems and providing reassurance. Treatment options for post-concussive headaches can be variable. Not a lot of research is available on the use of medications in the management of post-concussive headaches. Management involves treatment of the symptoms, including analgesics, migraine-specific medication (e.g., tricyclic antidepressants, propranolol), psychotropic medications, and counseling to manage psychosocial symptoms. Most patients have a quick recovery (within weeks), but some patients may have prolonged symptoms.

Trigeminal neuralgia results in head/facial pain coming from one or more of the trigeminal nerve branches. Classically the pain is unilateral, brief, stabbing, or lancinating that is sudden in onset. Imaging, typically with an MRI, is sometimes done to distinguish primary from secondary trigeminal neuralgia. The primary disease has no identifiable lesion causing the symptoms. Secondary causes of trigeminal neuralgia include acoustic neuromas, multiple sclerosis, cerebral aneurysms, and trigeminal neuromas. The secondary disease is more common if there is bilateral involvement; it occurs at a younger age; or if there is associated sensory loss. Conditions that may mimic trigeminal neuralgia include dental pain, multiple sclerosis, herpes zoster, or atypical headaches. Treatment for the pain of trigeminal neuralgia includes carbamazepine and oxcarbazepine. For those who are intolerant or non-responsive to these agents, baclofen or lamotrigine can be used. Surgical options are sometimes tried for refractory cases.

Peripheral neuropathy can come from many etiologies, including diabetes, cancer, alcohol, and HIV. Peripheral neuropathy typically presents with distal sensory loss, weakness, numbness, or burning. The presentation may be variable. Neuropathy due to diabetes is one of the more common types of neuropathies. Many forms of diabetic neuropathy exist, including symmetric polyneuropathy, radiculopathies, autonomic neuropathy, and mononeuropathies. They typically result in symptoms that begin in the lower extremities. Sensory symptoms are seen first, followed by motor symptoms. Patients complain of a gradual sensory loss, numbness, a burning sensation and pain in the feet, and mild gait abnormalities. Over time weakness may develop, and a "stocking and glove" distribution of sensory loss may occur. Physical exam findings depend on which nerve fibers are involved. Diagnostic tests that help define a neuropathy include conduction studies such as electromyogram or nerve condition studies. Treatment of neuropathies includes treating the underlying disease (e.g., controlling blood sugar in diabetes) and medications to treat the symptoms. Medications used to manage neuropathy pain include tricyclic antidepressants, duloxetine, gabapentin, pregabalin, carbamazepine, topiramate, tramadol, and NSAIDs.

Post-herpetic neuralgia is pain that presents after a herpes zoster infection caused by the varicella-zoster virus. Certain groups are at higher risk of developing pain after a herpes zoster infection. These include older individuals, those with higher levels of acute pain during the acute infection, and those with a more severe rash (Bajwa & Ortega, 2019). Herpes zoster is an infection that starts with a sharp, burning, stabbing pain that follows a dermatome. A rash will be seen a few days later along the same dermatome. Commonly affected dermatomes include the lumbar, thoracic, cervical, and trigeminal nerves. After the rash abates, some individuals develop pain along the same dermatome that persists longer than four months. Pain may persist for years or even throughout life. Allodynia is often seen in those with post-herpetic neuralgia.

Post-herpetic neuralgia is commonly treated with tricyclic antidepressants, pregabalin, and gabapentin. Topical capsaicin or lidocaine can be used. Opioids are sometimes used but should be used cautiously. They are considered second or third-line options and are sometimes used while the TCAs, pregabalin, and gabapentin take effect, then tapered. If all other options are not effective, the use of intrathecal glucocorticoids may be considered.

Back Pain

Most cases of back pain are non-specific and will improve within a few weeks with conservative treatment, but some people develop chronic pain. Those more likely to develop chronic back pain include those with functional impairment, poor health, comorbid psychiatric conditions, maladaptive pain-coping behaviors, and non-organic signs – such as pain in the low back when pressing directly on the head (Wheeler et al., 2019).

Less than one percent of patients with back pain have a serious cause of back pain, and less than ten percent have specific etiologies (Robinson & Kothari, 2019). When back pain is present, it is important to rule out any serious pathologies. Certain red flags suggest serious pathologies (see table below).

A complete history and physical exam are important parts of the exam to rule out serious causes of back pain and help identify the cause.

Certain more urgent conditions require direct imaging with an MRI and referral, including those with any red flags. Those who have not improved after 4-6 weeks of conservative therapy may be considered for imaging. Patients with conditions that may benefit from surgery or epidural injections should have imaging. Other conditions that are helped by imaging include osteoarthritis and ankylosing spondylitis.

Back pain should not be treated with bed rest, but modifying activity slightly to account for the pain is appropriate. Oral analgesics should be used short-term to provide pain control. Re-evaluation should occur at four weeks to evaluable improvement, evaluate for any needed testing, and reevaluate the need for pain medications.

Initial oral agents should include NSAIDs for 2-4 weeks. Those with an allergy or contraindication to NSAIDs may consider acetaminophen. When pain is not controlled with NSAIDs, the use of a muscle relaxant may be considered. For those who cannot take a muscle relaxant, the combination of an NSAID and acetaminophen is an option.

The use of opioids and tramadol should be used very judiciously in acute low back pain and only in those who are not getting pain control from other agents or contraindications to those other agents.

Physical therapy can be used for acute low back pain but is more often for chronic low back pain. Education is one of the most important aspects of managing back pain. Patients should be educated on the causes of back pain, the expected course, its encouraging prognosis, the value of diagnostic testing, treatment options, and when to contact their health care provider.

Back Pain Red Flags
  • New bowel or bladder incontinence
  • Saddle anesthesia – loss of sensation in the perineum, buttocks, and inner thighs
  • Severe neurological deficits
  • Weight loss
  • New-onset over age 50 years old or under 18 years-old
  • Progressive motor deficit
  • Night pain or rest pain
  • Fever – concern for infection – recent urinary tract infection or history of intravenous drug use
  • Current or recent cancer diagnosis or major risk factor for cancer
  • Pain persists beyond six weeks
  • Suspected vertebral fracture

Specific Cases of Back Pain

Acute disc herniation with radiculopathy in the lower back (lumbosacral spine) is a common diagnosis. The five lumbar vertebral bodies are movable, while the five sacral vertebras are fused. Below each vertebra, a pair of neural foramina (spinal nerve roots) exits that have the same number as the vertebra body. For example, the L5 nerve root exits between the L5 and S1 vertebral bodies.

The most common cause of lumbosacral radiculopathy is a herniated disc or degenerative arthritis leading to stenosis of the neural foramina. Other causes of radiculopathy include congenital abnormalities, infection, and cancer.

Radiculopathy can occur at any nerve root, but L5 or S1 impairment is the most common. L5 radiculopathy is associated with back pain that radiates down the lateral aspect of the leg into the foot. The exam shows reduced dorsiflexion, foot inversion and eversion, and reduced toe extension. The reflexes are typically normal in L5 radiculopathy.

S1 radiculopathy presents back pain that radiates down the posterior aspect of the leg into the foot. The exam shows reduced strength in leg extension and plantar flexion. There is a reduced sensation on the lateral foot and the posterior part of the leg. The ankle reflex is reduced or absent.

It is not necessary to perform an emergent MRI on patients with suspected lumbar or sacral radiculopathy if the clinician does not suspect a serious underlying cause (e.g., cauda equina syndrome, cancer, epidural abscess) of the radiculopathy. If symptoms persist, worsen, do not respond to conservative therapy, or procedures are considered, the use of imaging with an MRI may be considered. Those with severe or unrelenting findings with imaging results not suggestive of an underlying cause should undergo electromyography and nerve conduction studies. In some cases, a lumbar puncture is done.

Case Study 2

Maggie T is a 40-year-old secretary who presents to her primary care provider with back pain for the last three weeks. The pain started after she lifted a heavy box at work. Her self-management regime included bed rest and taking acetaminophen, alternating with ibuprofen for the last three weeks. She reports that the pain is not getting any better.

The pain is described as aching and diffusing along her lower back. She reports that the pain is worse with walking and prolonged standing or sitting and is relieved when lying down. She reports that the pain radiates into her right buttock but not down the leg.

Chris is generally healthy. The only medication that she takes regularly is sertraline for depression. She has never had any surgeries and has no allergies to medications.

On physical exam, her vitals are stable, and she appears comfortable. She walks with a slight limp. The exam shows diffuse tenderness across her lumbar spine. There is no deformity, the straight leg raise is normal, the sensation is intact to the lower extremities, and the remaining aspects of her exam show no focal neurological finding. Recent labs demonstrated a normal blood count and normal liver and renal function.

Her primary care physician recommends that she go to physical therapy, prescribes diclofenac 50 mg three times a day for three weeks, and encourages her to use acetaminophen for breakthrough pain.

At the three-week follow-up, Chris is doing better. Her primary care physician recommends continued home exercises as recommended by the physical therapist and the use of acetaminophen for pain; the NSAID is stopped at this time as it is likely limited if any inflammation contributes to the pain.

This case is typical of back pain; it is essentially resolved within six weeks. The pain was caused by an acute injury with muscle spasms, causing pain in the buttock. Radicular pain was not present. Radicular pain would be present if inflammation, compression, or injury to a spinal nerve root.

The use of imaging is not indicated in this case because there were no red flags. Typically, this type of back pain responds to simple analgesics; the use of opioids is unnecessary. Acetaminophen is preferred for analgesia because of its relatively safe profile. The use of an NSAID may be needed because of its anti-inflammatory effect. At times, short-term use of a muscle relaxer may be helpful for muscle spasm that often contributes to this type of acute pain. Tramadol is often used in cases of mild acute pain, but its potential abuse should be relegated to a second or third-line option. In this case, Chris is also on sertraline, and there is a potential interaction between tramadol and sertraline.

The goal, in this case, is to minimize disability and return Chris to her baseline function as soon as possible. Relative rest may be appropriate at first, but prolonged bed rest will contribute to deconditioning and stiffness and prolong recovery. The patient with acute low back pain should have exercises to strengthen the low back, stomach, and other core muscles and stretch the low back and legs.

Appropriate health care for back pain will quickly get patients back to normal functioning while minimizing the risk of dangerous treatment options.

Neck Pain

Neck pain can occur from multiple pathologies, including trauma, muscle strain, or disc pain. Most cases of neck pain will resolve within three weeks. Initial treatments are conservative, including oral analgesics (acetaminophen or NSAIDs for mild or moderate pain; short-term opioids for severe pain), posture modification, and exercise.

Chronic neck pain has multiple treatment options. The use of a long-term cervical collar is not recommended. The use of a cervical collar to manage severe pain for less than three hours a day for a maximum of 2 weeks may be considered. Physical therapy and home exercises should be used.

Pharmacological options for chronic pain include acetaminophen; NSAIDs; a low-dose antidepressant, especially in those with pain that interrupts sleep; a muscle relaxant may be considered for those with muscle spasms, and rarely opioids.

Other options for pain management include trigger point injections, cervical medial branch blocks, TENS units, and radiofrequency neurotomy. A surgical evaluation may be considered in those with myelopathy or neurological symptoms associated with radiculopathy.

Cervical radiculopathy often resolves on its own. The initial treatment in those who have obvious signs/symptoms of cervical radiculopathy includes pain control, often with non-steroidal anti-inflammatory medications. At times, the use of oral corticosteroids to reduce inflammation is considered. When the pain is reasonably controlled, physical therapy is initiated.

After conservative treatment, some patients may have recurrent symptoms even if there is an initial improvement. At this point, conservative treatment should again be initiated except in the cause of significant motor deficit or myelopathy.

Confirmed cervical radiculopathy with severe symptoms that have not responded to conservative therapy can be managed with epidural steroid injections under fluoroscopic guidance unless there is a progressive neurological deficit.

No firm evidence exists that surgery for cervical radiculopathy provides significant benefits. Some individuals will derive benefit from surgery, while others will not. Certain individuals should have a surgical evaluation, including those with cervical nerve root compression on imaging, persistent radicular pain after 6-12 weeks of conservative treatment, signs/symptoms of cervical radiculopathy, or progressive motor weakness that impairs function (Robinson & Kothari, 2019).

Complex Regional Pain Syndrome

Complex region pain syndrome (CRPS) is broken down into types I and II. It is a disorder of the extremities illustrated by regional pain that is inconsistent in degree or time to the expected course of pain. The pain is localized around a certain territory.

The primary clinical manifestation is pain typically described as stinging, burning, or tearing and is exacerbated by movement, temperature variation, stress, or any contact. Also, some individuals have allodynia or hyperalgesia. The patient may also notice differences in skin color or temperature. The affected side may be more edematous or sweat more when compared to the other side. Limb movement is typically impaired by pain, edema, or contractures. The patient with CRPS may also have unilateral variations in hair or nail growth along with skin atrophy.

The progression of the condition is variable over time. The underlying pathology is not well understood but may include inflammation and changes in pain perception in the central nervous system.

CRPS I is the more common type diagnosed when the typical symptoms are present and there is no evidence of a peripheral nerve injury. CRPS II is less common and is present when there is evidence of a peripheral nerve injury.

CRPS is more commonly seen in women. It is often associated with some acute event that starts the syndrome. This syndrome may include trauma, such as a broken bone or a crush injury. The diagnosis is made on a clinical exam after other conditions are ruled out.

Treatment of CPRS should involve a multidisciplinary approach, including physical and occupational therapy, physiological interventions, and pharmacotherapy. Pharmacologic options include NSAIDs, tricyclic antidepressants, gabapentin, or topical treatments (lidocaine or capsaicin). Other less common options include calcitonin, glucocorticoids, alpha-adrenergic agonists/antagonist (e.g., prazosin, clonidine), ketamine, and opioids. Multiple interventional approaches may be considered, including regional sympathetic nerve blocks, trigger/tender point injections, and spinal cord stimulation.

Phantom Limb Pain

Phantom limb pain is aching, burning or shock-like pain where an amputated limb used to be. Before diagnosing phantom limb pain, it is important to rule out other causes of the symptoms, such as infection or wound on the stump, ischemia, or neuroma. The incidence of this condition is variable, and it is hypothesized that not controlling pain before and after the surgery increase the risk for phantom limb pain. Multiple agents are helpful in the management of phantom limb pain, including acetaminophen, NSAIDs, TCAs, and gabapentin. In addition to medication, non-pharmacologic methods to manage pain include TENS units, mirror therapy (which helps resolve the visual-proprioceptive disconnect), biofeedback, and occasionally surgical interventions.

Cancer Pain

Pain is very prevalent in cancer. It is present in up to one-half of patients when first diagnosed with cancer and, according to some estimates, up to 100 percent of people with advanced cancer.

Pain in cancer can be acute or chronic. Acute pain is seen during interventions such as surgery, tissue injury, or radiation therapy. Acute pain can also be felt secondary to cancer, such as an obstructed bowel, a perforated bile duct, bleeding from liver cancer, or a pathological fracture. Chronic pain during cancer is typically related to the tumor itself or as a complication of treatment.

Neuropathic pain is also seen in cancer patients. Neuropathic pain in cancer can arise from the tumor pressing on a nerve or nerve plexus. Also, neuropathic pain can result from the treatment, as many chemotherapeutic agents or radiation therapy can potentially cause nerve injury. Many conditions resulting in neuropathic pain - such as herpes zoster and post-herpetic neuralgia - are relatively common in cancer patients.

Management of cancer pain is typically aggressive. The use of opioids is common in chronic cancer pain, and doses should be titrated to find effective pain control. Agents commonly used include hydromorphone, morphine, oxycodone, and hydromorphone. These agents are preferably given orally or transdermally. Dosing is commonly started with short-acting agents, but for those with chronic pain switching over to a long-acting formulation is preferred with the continued use of short-acting agents for break-through pain. The dose for breakthrough pain is typically about 10 percent of the basal daily opioid dose. Individuals who need rapid titration do well with the use of opioids given via infusion by the IV or SC route.

While morphine is traditionally a common agent used, other agents have a good effect in certain situations. For those with swallowing difficulty or poor ability to absorb from the GI tract, the use of fentanyl can be used. Hydromorphone or fentanyl is recommended for those with renal insufficiency.

Other Pain Syndromes

Irritable bowel syndrome (IBS) has multiple presentations. The most common symptoms include abdominal pain and altered bowel habits (constipation, diarrhea, alternating constipation, and diarrhea). The abdominal pain of IBS improves with bowel movements, and the onset of pain is associated with a change in stool frequency and the form of the stool (Wald, 2019).

To diagnose the condition, the criteria of recurrent abdominal pain occurring at least one day a week for the last three months are associated with two of the following three:

  1. Change in the form of stool
  2. Change in the frequency of stool
  3. Pain-related to the bowel movement

IBS is not associated with weight loss, anemia, or rectal bleeding and does not wake the person from sleep. If no alarm features are present, endoscopic evaluation is not necessary.

Alarm Features in IBS
  • Rectal bleeding
  • Weight loss
  • Nocturnal symptoms
  • Family history of colorectal cancer, celiac sprue, or inflammatory bowel disease
  • Unexplained iron deficiency anemia

For individuals with mild and intermittent symptoms, lifestyle and dietary modifications, such as avoiding irritating foods, including beans, cabbage, and onions, may be used. Other dietary changes that may be helpful include avoiding large meals, avoiding caffeine, eating regularly, and limiting fat intake.

In patients with mild to moderate symptoms that do not respond to lifestyle changes or those with severe symptoms, pharmacotherapy can be considered in addition to lifestyle changes. Pharmacotherapy should focus on the treatment of predominant symptoms. Medication trials should be re-evaluated at two to four weeks.

When constipation is the predominant symptom, psyllium or polyethylene glycol should be tried. The next line options for constipation-predominant IBS include linaclotide and lubiprostone.

For patients with abdominal pain, the use of antispasmodics (e.g., dicyclomine, hyoscyamine) may be used. Antidepressants can be added when abdominal pain persists when using antispasmodics. Antidepressants are helpful in those with IBS and depression.

When IBS presents with diarrhea, antidiarrheal agents can be used. If these are not effective, bile acid sequestrants are added. In select cases, rifaximin is considered.

Fibromyalgia

Fibromyalgia (FMS) is a condition characterized by chronic widespread musculoskeletal pain. Patients also complain of fatigue, sleep disturbances, psychiatric symptoms, cognitive disturbances, and multiple other somatic complaints. The etiology and pathophysiology are unclear.

In FMS, pain is typically diffuse and persistent. It is often described as stiffness, deep aching, soreness, burning, or throbbing. Patients typically report persistently present pain, but the intensity may vary. Poor sleep, excessive stress, or exposure to cold may exacerbate the pain. Generally, pain is worse in the morning and improves throughout the day. Pain commonly affects the neck, shoulders, back, arms, legs, and chest wall.

The patient looks well, and no objective findings characterize the disease on the exam. Also, laboratory and radiological exams are normal in fibromyalgia.

Some have suggested that fibromyalgia is a form of central sensitization (Boomershine, 2015). Likely there is a genetic predisposition to the condition. It is thought that certain stressors such as sleep disturbance, infections, or trauma (emotional and physical) may lead to fibromyalgia.

Fibromyalgia is more common in women and is six times more common when compared to men. The prevalence is about 2-3 percent in the United States. It is the most common cause of generalized musculoskeletal pain in females aged 20 to 55.

Signs and Symptoms

  • Widespread musculoskeletal pain that affects both sides of the body
  • Fatigue often occurs when waking up and in the mid-afternoon
  • Poor sleep (non-refreshed/non-restorative sleep or difficulty falling or staying asleep)
  • Numbness/tingling is often seen in the extremities
  • Headache, which may include migraine or tension headache
  • Cognitive disturbances such as problems with attention
  • Psychiatric disturbances including depression, anxiety, and posttraumatic stress disorder
  • Other conditions and symptoms associated with FMS include restless leg syndrome, obstructive sleep apnea, bladder irritability, chronic fatigue syndrome (CFS), Raynaud phenomenon, symptoms of autonomic dysfunction (e.g., orthostatic tachycardia), vulvodynia, temporomandibular syndrome, chest wall pain, irritable bowel symptoms (abdominal pain, diarrhea, constipation), dry eye, night sweats, shortness of breath and palpitations

Physical Exam Findings

  • Soft tissue tenderness may be variable. When palpating a tender point, pressure should equal the amount of pressure to whiten the nail bed.
  • The exam should rule out any other causes of pain - synovitis or joint tenderness may suggest another disease.
  • Mild sensory or motor problems may be noted in fibromyalgia.
  • No visible inflammation is seen, but the patient often complains that their joints are swollen.

In 1990, the American College of Rheumatology (ACR) developed classification criteria. It identified nine pairs or 18 tender points and said that 11 of 18 points should be positive to diagnose FMS.

In 2010, a new criterion to diagnose FMS was published. It did not recommend using the tender point examination to diagnose FMS as they are difficult to obtain, and many clinicians have not been trained in their use. It uses a widespread pain index (WPI) and a symptom severity (SS) scale to diagnose FMS. The WPI assesses the number of painful body regions from 19 areas. The SS score assesses the amount of fatigue, cognitive symptoms, the degree of waking up feeling unrefreshed, and the number of general somatic symptoms.

Patients with FMS often complain of hurting or feeling like they have the flu. It is diagnosed in those with chronic pain and no hint of muscle inflammation.

Differential FMS diagnoses include osteoarthritis, autoimmune disease, rheumatoid arthritis, systemic lupus erythematosus, hypothyroidism, inflammatory myopathy, systemic inflammatory arthropathies, spondyloarthritis, Ankylosing spondylitis, myositis, and polymyalgia rheumatic.

The laboratory evaluation rules out other conditions and should include a complete blood count (CBC), an erythrocyte sedimentation rate (ESR) or C-reactive protein (CRP). Other tests may be ordered individually, such as a thyroid-stimulating hormone test (if hypothyroidism is suspected) or a creatine kinase (if inflammatory myopathy is suspected). Testing for other rheumatologic diseases (an antinuclear antibody test and rheumatoid factor) should be done only if clinically indicated.

Treatment of FMS is challenging at best. It typically includes a combination of non-pharmacological and pharmacological treatments implemented by a multidisciplinary team. The treatment approach must be individualized. The treatment goals are to reduce pain and other symptoms of the disease.

Education is a critical step in the treatment of FMS. The condition must be explained to the patient, including treatment approaches. Key aspects of patient education include:

  • Sleep hygiene
  • Symptoms will vary over time – fatigue and pain typically persist
  • It is a benign disease which should be taught to the patient. The patient must understand that the disease will not deform the patient, lead to a cosmetic issue, or become life-threatening
  • Emotional or physical stress may increase symptoms. The patient should be taught stress-reduction and relaxation techniques to help in the management of the condition
  • While infection may be a precipitating factor, it is not a persistent infection that causes the symptoms
  • Neurohormonal abnormalities may account for fatigue, pain, mood disturbance, and sleep disturbance
  • Exercise should be encouraged but may increase pain – especially early in an exercise program
  • Other non-pharmacological methods to manage FMS include supervised physical therapy, cognitive behavioral therapy, biofeedback, tai chi, or yoga

Medications are often used in the management of FMS. Typically, non-pharmacological methods are used first, and when they are not effective, the addition of medication is considered. Commonly used medications include low-dose tricyclic antidepressants, selective serotonin reuptake inhibitors, pregabalin, duloxetine, cyclobenzaprine, and milnacipran. When utilizing medications, the dose should be started low and built up gradually.

Amitriptyline, milnacipran, pregablin, and duloxetine are fist line agents for fibromyalgia. Still, most patients do not find significant improvement (some improvement was noted with sleep and pain, but fatigue and quality of life were only minimally improved) with these medications, and many have significant side effects (Goldenberg, 2020).

When first-line agents do not work, a combination of medications can be tried. For example, duloxetine in the morning and a tricyclic antidepressant before bed is one such combination. Combinations of medications work through different mechanisms of action and focus on different symptoms.

At times, the addition of analgesics or anti-inflammatory medication can be tried. Using acetaminophen, NSAIDs, or tramadol may be considered to target pain when more traditional FMS agents do not work. Generally, opioids should be avoided in FMS.

Rheumatoid Arthritis

Rheumatoid arthritis (RA), a chronic destructive, sometimes deforming disease, attacks the collagen in the body, especially in the joints. Rheumatoid arthritis is associated with widespread symptoms such as fatigue, fever, poor appetite, nerve damage, and increased size of the spleen and lymph nodes. RA can irreversibly damage joints. Therefore, early diagnosis and treatment to control inflammation can improve the outcomes of the disease.

Treatment options include psychosocial care, patient education, therapy, and pharmacologic treatment. A rheumatologist should be involved in caring for patients with RA as disease-modifying antirheumatic drugs (DMARD) are complex to use. If therapy is started soon, the patient will experience better outcomes. DMARD therapy is complex, requires much monitoring, and is beyond this article's scope.

The use of NSAIDs and glucocorticoids are also used in the management of RA. They can be used as bridging therapy to get quick control of inflammation until the DMARDs take effect and can be used for pain control.

Osteoarthritis

Osteoarthritis (OA) is the most common cause of disability in the older population.

Arthritis affects 32.5 million adults and costs more than $140 billion annually in the United States (CDC, 2020). As the population ages, the burden of OA will increase. Managing arthritis improves mobility, decreases falls, decreases death rates, and improves the quality of life.

Osteoarthritis is a joint disease with deterioration of the joint and abnormal bone formation. OA is present when the endings of the bones - called cartilage, which normally cushion the bones - no longer do their jobs. The ends of the bones rub together, and the cartilage wears away.

Treatment of osteoarthritis focuses on pain control and maintaining function. Soon there may be treatments available to reverse or even cure the disease process, but symptom control is currently the only option. Treatment focuses on medications, and non-medication means controlling pain and minimizing disability.

Non-drug treatment is first-line management as it bypasses drugs' negative effects on the body. Non-drug treatments include exercise, nutrition, physical and occupational therapy, heat and cold treatments, ultrasound, weight loss, magnets, and patient education.

The American Academy of Orthopedic Surgeons does not recommend for or against using acetaminophen. Their position paper reports that acetaminophen has no benefit over placebo, so they do not recommend this treatment. They do acknowledge that the side effect profile of acetaminophen is less toxic than non-steroidal anti-inflammatory agents (NSAIDs) (Meiyappan et al., 2020).

NSAIDs are considered more effective in relieving hip and knee pain in osteoarthritis (Bannuru et al., 2015). Like acetaminophen, they act synergistically with opioids. Others suggest that acetaminophen is the least effective option compared to NSAIDs or the combination of glucosamine and chondroitin. They acknowledge that the acetaminophen's side effect profile is less toxic than NSAIDs. NSAIDs are considered more effective than acetaminophen in relieving knee/hip pain in osteoarthritis (Lozada, 2020).

NSAIDs, such as ibuprofen (Motrin®, Advil®), naproxen sodium (Aleve®, Naprosyn®), choline and magnesium salicylates (Trilisate®), diclofenac sodium (Voltaren®, Voltaren® XR), celecoxib (Celebrex®), meloxicam (Mobic®), and nabumetone (Relafen®), are recommended by the American Academy of Orthopaedic Surgeons. These medications have more side effects than acetaminophen.

Topical NSAIDs, such as diclofenac, may be used, especially if the disease is localized to one area. Topical agents are associated with a significantly less adverse event profile than systemic agents.

Other topical agents can provide significant relief for patients with OA. Capsaicin (Zostrix®) decreases the neurotransmitter called substance P, which is involved in the transmission of pain. Capsaicin is applied three to four times a day. It takes Capsaicin a few weeks before it provides significant pain relief. Hands should be washed after contact with the substance.

Another topical agent sometimes used to treat localized pain is the lidocaine (Lidoderm®) patch. This medication is not approved by the Food and Drug Administration for use in osteoarthritis but is often used. It is a small patch applied to the skin around the painful joint for no more than 12 hours daily.

Other options include tramadol, codeine, hydrocodone, hydromorphone, oxycodone, fentanyl, and morphine.

Intra-articular steroid injections can be used for painful joints. This treatment involves placing a needle directly into the arthritic joint and injecting a steroid and a numbing agent. Before administering the medication, the aspiration of synovial fluid may occur. These are highly effective treatments, but their length of effect is variable from weeks to months. A reduction in pain may be seen as soon as one week after the injection. Corticosteroid injections have the potential to damage cartilage, and no more than four injections per year should be given (O’Dell & Matteson, 2018).

Intra-articular hyaluronic acid is sometimes used to mimic the joint lubricant – which is often reduced in those with OA - that naturally occurs in the knee. It is classified as a medical device and not a drug. Products include Hyalgan®, Supartz®, Orthovisc®, Euflexxa®, and Synvisc®. The American Academy of Orthopaedic Surgeons does not recommend treatment, but the effects of these drugs may be more beneficial than once thought. Numerous reports that hyaluronic acid injections are safe and similar if not more effective than nonsteroidal anti-inflammatory drugs (Miller et al., 2016). Side effects include discomfort, swelling, and pain at the injection site.

When medical treatment fails, surgery is the next option. Surgical options include arthroscopy, osteotomy, total joint arthroplasty, or joint fusion.

Myofascial Pain Syndrome

A myofascial pain syndrome is a group of conditions that involve muscle, tendon, ligament, fascia, bursa, or subcutaneous tissue. Diagnoses commonly seen in myofascial pain syndrome include tendinitis, bursitis, enthesitis, fasciitis, and regional myofascial pain disorder. Some are self-limiting, while others are more chronic.

Tendinitis commonly occurs due to overuse and presents with local discomfort and inflammation. Bursitis is inflammation of the bursa, which are small pads filled with fluid. It is caused by infection, systemic disease, or repetitive injury. Enthesitis is when there is inflammation where the tendon inserts into the bone. Common diagnoses in this condition include plantar fasciitis and Achilles tendonitis.

Regional myofascial pain presents taut bands in the skeletal muscle or the fascia. These bands are indurated and hurt when pressed on. They result from acute trauma, minor microtrauma, or chronic strain.

Myofascial pain syndrome is a wide range of conditions typically treated symptomatically. Many of these conditions are caused by inflammation and are best treated with anti-inflammatory agents to treat the pain and inflammation.

Conclusion

Pain is a disagreeable sensory and emotional experience connected with actual or potential tissue damage or explained in terms of such damage. Many conditions have the potential to cause pain. Understanding these conditions, how to assess them, and how to treat them are a vital part of adequately managing the pain. In the current health care system, much pain is not even addressed. Many regulatory agencies have implemented guidelines within the health care system to help with addressing the pain epidemic.

The healthcare team's role is to perform a good initial pain assessment and an ongoing assessment of pain. Proper pain management requires a team approach to assessing and treating pain. Many options are available for the management of pain, including non-pharmacological options, non-opioid medications, opioid medications, and adjunctive medications. Opioid analgesics, particularly good at managing pain, have led to many social and legal problems, including overuse and diversion.

The healthcare team is also responsible for partnering with the patient to manage the pain properly. Each health care team member has a role in the management of pain. If health care team members perform their role, and the patient takes an active role in his/her care, the adequate treatment of pain is a very attainable goal.

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