Introduction
Chronic pain and opioid use and abuse is a significant problem in the United States and in Florida.[1] Over one-quarter of United States citizens suffer from chronic pain.[2] It is among the most common complaints seen in an outpatient clinic and the emergency department. The failure to manage chronic pain, as well as the possible complication of opioid dependence related to treatment, can result in significant morbidity and mortality. One in five patient complaints in an outpatient clinic is related to pain, with over half of all patients seeing their primary care provider for one pain complaint or another. It is paramount that providers have a firm grasp on the management of patients with chronic pain. As a country, the United States spends well over 100 billion dollars a year on healthcare costs related to pain management and opioid dependence.[3] Pain-related expenses exceed those for the costs of cancer, diabetes, and heart disease combined.[4] How a patient's chronic pain gets managed can have profound and long-lasting effects on a patient's quality of life.
The International Association for the Study of Pain defines chronic pain as any pain lasting longer than three months.[5] There are multiple sources of chronic pain. Combination therapy for pain includes both pharmacological therapies and nonpharmacological treatment options. There is a more significant reduction in pain with combination therapy compared to a single treatment alone. Escalation of pharmacological therapy is in a stepwise approach. Comorbid depression and anxiety are widespread in patients with chronic pain. Patients with chronic pain are also at increased risk for suicide. Chronic pain can impact every facet of a patient's life. Thus learning to diagnose and appropriately manage patients experiencing chronic pain is critical.[6]
Unfortunately, studies have revealed an inherent lack of education regarding pain management in most professional schools and training programs. Many schools have committed to opioid-related education and training by incorporating the Centers for Disease Control and Prevention guidelines for prescribing opioids for chronic pain into the medical school curriculum.
Appropriate opioid prescribing includes prescribing sufficient opioid medication through regular assessment, treatment planning, and monitoring to provide effective pain control while avoiding addiction, abuse, overdose, diversion, and misuse. To be successful, clinicians must understand appropriate opioid prescribing, assessment, the potential for abuse and addiction, and potential psychological problems. Inappropriate opioid prescribing typically involves not prescribing, under prescribing, overprescribing, or continuing to prescribe opioids when they are no longer effective.
The American Society of Addiction Medicine describes addiction as a treatable chronic disease that involves environmental pressures, genetics, an individual's life experiences, and interactions among brain circuits. Individuals that become addicted to opioids or other medications often engage in behaviors that become compulsive and result in dangerous consequences. The American Society of Addiction Medicines notes that while the following should not be used as diagnostic criteria due to variability among addicted individuals, they identify five characteristics of addiction:
Craving for drug or positive reward
Dysfunctional emotional response
Failure to recognize significant problems affecting behavior and relationships
Inability to consistently abstain
Impairment in control of behavior
Unfortunately, for most health providers, understanding of addiction is often confusing, inaccurate, and inconsistent due to the broad range of perspectives of those dealing with patients suffering from addiction. While a knowledge gap is present among healthcare providers, it is equally prevalent in politicians writing laws and law enforcement attempting to enforce the laws they write. Payers are responsible for the expenses associated with the evaluation and treatment of addiction. Persistent lack of education and the use of obsolete terminology continue to contribute to a societal lack of understanding for effectively dealing with the challenges of addiction.
In the past, the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders defined "addiction," "substance abuse," and "substance dependence" separately. The result was provider confusion contributed to the under-treatment of pain. Over time, the manual has eliminated these terms and now uses "substance use disorder," ranging from mild to severe.
Unfortunately, there are numerous challenges in pain management, such as both underprescribing and overprescribing opioids. The concerns are particularly prominent in patients with chronic pain and have resulted in patients suffering from inadequately treated pain while at the same time there has been a development of concomitant opioid abuse, addiction, diversion, and overdose. As a result, providers are often negatively influenced and fail to deliver appropriate, effective, and safe opioids to patients with chronic pain. Providers have, in the past, been poorly trained and ill-informed in their opioid prescribing. To make the challenges even worse, chronic pain patients often develop opioid tolerance, significant psychological, behavioral, and emotional problems, including anxiety and depression related to under or overprescribing opioids.
Clinicians who prescribe opioids face challenges that involve medical negligence in either failure to provide adequate pain control or risk of licensure or even criminal charges if it is perceived they are involved in drug diversion or misuse. All providers that prescribe opioids need additional education and training to provide the best patient outcomes and avoid the social and legal entanglements associated with over and under prescribing opioids.
Prescribers of Controlled Substances In Florida
Provider Opioid Knowledge Deficit
There are substantial knowledge gaps around appropriate and inappropriate opioid prescribing, including deficits in understanding current research, legislation, and appropriate prescribing practices. Providers often have knowledge deficits that include:
Understanding of addiction
At-risk opioid addiction populations
Prescription vs. non-prescription opioid addiction
The belief that addiction and dependence on opioids is synonymous
The belief that opioid addiction is a psychologic problem instead related to a chronic painful disease
With a long history of misunderstanding, poor society, provider education, and inconsistent laws, the prescription of opioids has resulted in significant societal challenges that will only resolve with significant education and training.
Misuse of Controlled Substances
Unfortunately, the misuse of controlled substances resulting in morbidity and mortality is rampant.[7] According to the National Survey on Drug Use and Health,2016, performed by the U.S. Department of Health and Human Services, over 10 million people misuse prescription pain medications, and over 2 million misuse sedatives, stimulants, and tranquilizers each year. The same study found that the most common reason for misuse is for the treatment of physical pain. The Center for Disease Control estimates more than 40,000 people die each year die from an opioid overdose.
Controlled Substances
There are three common classes of controlled substances commonly misused: opioids, depressants, and stimulants.
Opioids
Opioids are prescribed for pain control by binding to mu-opioid receptors in the central nervous system reducing pain signals to the brain as well as receptors in the GI tract and respiratory system, and are used to treat pain, diarrhea, and cough.[8]
Common Opioids
Codeine - One of the most commonly taken opioid medications. It is at the center of the opioid addiction problem in the United States and thus is highly regulated. Its main indication is for pain and cough.
FDA-Approved Indication
Pain
Codeine plays a role in the treatment of mild to moderate pain. Its use is recognized in chronic pain due to ongoing cancer and palliative care. However, the use of codeine to treat other types of chronic pain remains controversial. Chronic pain, defined by the International Association for the Study of Pain, is pain persisting beyond the standard tissue healing time, which is three months.[1] The most prevalent causes of non-cancer chronic pain include back pain, fibromyalgia, osteoarthritis, and headache.
Non-FDA Approved Indications
Cough
Codeine is useful in the treatment of various etiologies producing chronic cough. Also, 46% of patients with chronic cough do not have a distinct etiology despite a proper diagnostic evaluation. Codeine produces a decrease in cough frequency and severity in these patients. However, there is limited literature demonstrating the efficacy of codeine in chronic cough. The dose can vary from 15 mg to 120 mg a day. It is, however, indicated in the management of prolonged cough (in specific populations like lung cancer) usually as 30 mg every 4 to 6 hours as needed.
Restless Leg Syndrome
Codeine is effective in treating restless leg syndrome when given at night time, especially for those whose symptoms are not relieved by other medications.
Persistent Diarrhea (Palliative)
Codeine and loperamide are equally effective, and the choice between them has its basis in the assessment of the physician evaluating the small but undoubted addictive potential of codeine versus the higher cost of loperamide, and an individual difference in patient's vulnerability to adverse effects.
Fentanyl - Transdermal patch and IV, commonly abused and used in mixture with other drugs. Fentanyl is a synthetic opioid that is 80-100 times stronger than morphine and is often added to heroin to increase its potency. It can cause severe respiratory depression and death, particularly mixed when mixed with other drugs or alcohol. It has a high addiction potential.[9]
Hydrocodone - Hydrocodone is a schedule II semi-synthetic opioid medication used to treat pain. Immediate-release (IR) hydrocodone is available as a combination product (combined with acetaminophen, ibuprofen, etc.) and is FDA approved for the management of pain severe enough to require an opioid analgesic and for which alternative (non-opioid) treatments are inadequate. Single-entity hydrocodone is only available in extended-release (ER) formulations. It is FDA approved to treat persistent pain severe enough to require 24-hour, long-term opioid treatment, and for which alternative treatments are inadequate. Hydrocodone is also an antitussive and indicated for cough in adults.[10]
Morphine Sulfate - FDA-approved usage of morphine sulfate includes moderate to severe pain that may be acute or chronic. Most commonly used in pain management, morphine provides significant relief to patients afflicted with pain. Clinical situations that benefit significantly by medicating with morphine include managing palliative/end-of-life care, active cancer treatment, and vaso-occlusive pain during sickle cell crisis. Morphine is widely used off-label for almost any condition that causes pain. In the emergency department, morphine is given for musculoskeletal pain, abdominal pain, chest pain, arthritis, and even headaches when patients fail to respond to first and second-line agents. Morphine is rarely used for procedural sedation. However, clinicians will sometimes combine a low dose of morphine with a low dose of benzodiazepine-like lorazepam for small procedures.[11]
Oxycodone - An opioid agonist prescription medication. The oxycodone immediate-release formulation is FDA-approved for the management of acute or chronic moderate to severe pain for which other treatments do not suffice, and for which the use of opioid medication is appropriate. The extended-release formulation is FDA-approved for the management of pain severe enough to require continuous (24 hours per day), long-term opioid treatment, and for which there are no alternative options to treat the pain. The oxycodone to morphine dose equivalent ratio is approximately 1 to 1.5 for immediate-release and 1 to 2 for extended-release formulations.[12]
Tramadol - Tramadol is an FDA approved medication for pain relief. It has specific indications for moderate to severe pain. It is considered a class IV drug by the FDA. Due to possible abuse and addiction potential, limitations to its use should be for pain that is refractive to other pain medication, such as non-opioid pain medication. There are two forms of tramadol: extended-release and immediate release. The immediate-release is not for use as an "as needed" medication; instead, it is for pain of less than a week duration. For pain lasting more than a week, extended-release is the therapeutic choice — the indication for extended-release is for pain control under 24-hour management or an extended period.
Off-label, the drug is useful for premature ejaculation and restless leg syndrome refractory to other medications. For the off-label use of tramadol for premature ejaculation, both sporadic and daily use is effective for the treatment of the condition. Patients indicate a preference for "as needed" therapy for premature ejaculation due to the lack of side effects compared to the daily use of tramadol.[13]
Addiction, Dependence, and Tolerance
While each of these terms is similar, providers should be aware of the differences.
Addiction - the constant need for a drug despite harmful consequences.
Pseudoaddiction - constant fear of being in pain, hypervigilance; usually, there is a resolution with pain resolution.
Dependence - physical adaptation to a medication where it is necessary for normal function and withdrawal occurs with lack of the medication.
Tolerance - lack of expected response to a medication increasing dose to achieve the same pain relief resulting from CNS adaptation to the medication over time.
Etiology
Most patients who suffer from chronic pain complain of more than one type of pain.[14] For example, a patient with chronic back pain may also have fibromyalgia. A significant percentage of patients suffer from a major depressive and generalized anxiety disorder. Over 67% of patients with chronic pain suffer from a comorbid psychiatric disorder.[15]
There are multiple categories and etiologies of types of pain, which include neuropathic, nociceptive, musculoskeletal, inflammatory, psychogenic, and mechanical.[6][16]
Neuropathic Pain
Peripheral neuropathic pain, as in the case of post-herpetic neuralgia or diabetic neuropathy
Central neuropathic pain - cerebral vascular accident sequella
Nociceptive Pain
Musculoskeletal Pain
Inflammatory Pain
Psychogenic Pain
Mechanical Pain
Opioid Manufacturers Role
Individuals and governments, including federal, state, and local municipalities, have successfully sued opioid manufacturers for their role in promoting the use of opioids. Purdue Pharma specifically has been found liable for the promotion of its sustained-release form of oxycodone.
[17]
Epidemiology
Acute and Chronic Pain
There are over 100 million people in the United States who would meet the criteria for chronic pain syndrome.[2] Over 50 million Americans suffer from debilitating chronic pain, and over 20 million indicate that pain interferes with their daily lives. Chronic regional pain is reported in 11.1 percent of chronic pain patients, while chronic back pain accounts for 10.1 percent, leg and foot pain 7.1 percent, arm and hand pain 4.1 percent, and headache 3.5 percent. There are reports of widespread pain in 3.6% of patients with chronic pain.[15] Elderly patients have been shown to receive up to 25% fewer pain medications than the average population.[18]
Chronic pain is estimated to cost over $600 billion annually in lost productivity and medical treatment. Lifetime chronic pain is common, with over 50% of adults being affected at some point in their lives. Over 40% of chronic pain patients indicated their pain is not controlled, and over 10% suffer long-term disabling chronic pain.
Research has shown the lifetime prevalence for chronic pain patients attempting suicide between 5% and 14%; suicidal ideation was approximately 20%.[19] Of the chronic patient patients who commit suicide, 53.6% died of firearm-related injuries, while 16.2% by opioid overdose.[20]
The incidence of chronic pain is increasing due to the prevalence of obesity-related pain conditions, increased survival of trauma and surgical patients, an aging population, and heightened public awareness of pain as a treatable condition.
Opioids
Opioids are the most used therapeutic agent for chronic pain and are derived synthetically from generally unrelated compounds. Opiates are derived from the liquid of the opium poppy either by direct refinement or by relatively minor chemical modifications. Both opioids and opiates act on three major classes of opioid receptors: mu, kappa, delta, and several minor classes of opioid receptors like nociceptin and zeta. Simplifying significantly, the mu receptors are thought to provide analgesia, respiratory suppression, bradycardia, physical dependence, gastrointestinal dysmotility, and euphoria. The kappa agonism can yield hallucinations, miosis, and dysphoria. The delta receptor likely has pain control and mood modulation effects, but some have suggested that mu agonism is necessary for the delta receptor to function strongly for analgesia.[21][22] The nociceptin receptor modulates brain dopamine levels and has clinical effects like analgesia and anxiolysis. The zeta receptor, also known as the opioid growth factor receptor, can modulate certain types of cell proliferation, such as skin growths, and are not thought to have many functions in modulating pain or emotion.[23][24]
In the past, providers in the United States rarely prescribed opioids for any condition except chronic cancer pain. This approach began to change in the 1990s. Dr. James Campbell addressed the American Pain Society (now bankrupt) in 1995 and urged healthcare providers to treat pain as the fifth vital sign.[25] The prescription of opioids for treating all chronic pain conditions has grown to the point that opioid sales have reached over 7 billion dollars. The United States currently consumes more than 80% of all opioids produced worldwide. With increased use, concomitant problems have developed, and the number of individuals abusing opioid analgesics has increased dramatically.[9][26]
Florida and Nationwide Opioid and Benzodiazepine Related Morbidity and Mortality
In the U.S., there are over 70,000 drug overdose deaths reported annually. There is a slight age-related decline in prescription-related opioid deaths in recent years, most likely attributed to increasing awareness of the problem by practitioners as well as the public. Opioids remain the most common cause of death related to an overdose, and deaths related to synthetic opioids such as fentanyl is rising.
According to the CDC, approximately 70% of the nearly 5,000 reported drug overdose deaths in Florida involve opioids. In Florida, synthetic opioids such as fentanyl remain stable but high. Deaths involving heroin and prescription opioids remain substantial in Florida.
Florida has seen a steady rise in use and related morbidity and mortality due to the use of heroin, synthetic cannabinoids, and novel psychoactive substances. While there has been a slight decrease in prescription opioid fatalities, at the same time, there has been an increase in overdose fatalities from opioid and non-opioid agents.[27][28]
According to the CDC, fatalities from benzodiazepines nationwide and in Florida are also significant, with alprazolam being the most common drug.
Florida Opioid Prescriptions
According to the CDC, Florida providers write 53.7 opioid prescriptions for every 100 persons, compared to the national average of 51.4 prescriptions. This rate has been declining.
Florida and National Neonatal Opioid Withdrawal Syndrome (NOWS) and Neonatal Abstinence Syndrome (NAS)
NOWS and NAS occur in women who use opioids in pregnancy. There is no accurate statistical reporting in Florida or the nation, but it is deemed a common cause of morbidity and mortality in infants. The commonly reported rate is 7 cases per 1,000 live births in the U.S. and 7.3 cases per 1,000 live births in Florida reported by the Healthcare Cost and Utilization Project (HCUP).
Florida and National HIV and Hepatitis C (HCV) Diagnoses Related To Injection Drug Use (IDU)
According to the CDC, nationally, about 10% of new HIV diagnoses are attributed to IDU; and in Florida, approximately 5 to 8% of new HIV diagnosis is attributed to IDU. Nationally, approximately 85% of new cases of HCV are attributed to IDU; and in Florida, reported findings are similar.
Pathophysiology
The pathophysiology of acute and chronic pain is complex and not completely understood. Research is ongoing. In general, the following provides an overview of the current understanding of pain pathophysiology.[6][15]
Acute Pain
It is caused by the activation of peripheral pain receptors and specific A-delta and C-sensory nerve fibers (nociceptors). It is commonly a response to tissue injury.
Chronic Pain
Chronic pain is usually related to ongoing tissue injury is thought to be caused by persistent activation of these pain fibers. Chronic pain may also develop from ongoing damage to or dysfunction of the peripheral or central nervous system which causes neuropathic pain.
Nociceptive Pain
Nociceptive pain receptors may be somatic or visceral. Somatic pain receptors are located in the subcutaneous tissues, fascia, connective tissues, endosteum, periosteum, joint capsules, and skin. Stimulation results in burning, dull, or sharp pain.
Visceral pain receptors are located in the viscera and connective tissue. Visceral pain due is usually due to obstruction of a hollow organ. This pain is deep, cramping, poorly localized, and may be referred to a remote site. Visceral pain from injury of connective tissue or organ capsules may be more localized and sharp.
Psychologic Factors
Psychologic factors in the modulation of pain intensity are highly variable. Culture, emotions, and thoughts and emotions affect an individual's perception of pain. Patients who suffer from chronic pain may also have psychological stress, particularly anxiety and depression. As a result of some syndromes being characterized as psychiatric disorders such as somatic symptom disorders defined by self-reported pain, patients are often mischaracterized as having a psychiatric disorder and are deprived of appropriate care. Pain may interfere with cognitive attention, concentration, the content of thought, and memory.
Multifactorial Pain Syndromes
Many pain syndromes are multifactorial; for example, cancer and chronic low back pain syndromes have a nociceptive component but may also involve neuropathic pain as a result of nerve damage.
Pain Modulation and Transmission
Pain fibers enter the spinal cord at the posterior root ganglia and synapse in the posterior horn. Fibers then cross to the contralateral side and travel up the lateral columns reaching the thalamus and, finally, the cerebral cortex. Repetitive stimulation from prolonged pain can sensitize neurons in the posterior horn of the spinal cord so that a minimal peripheral stimulus results in pain.
Peripheral and nerves at other levels of the central nervous system are sensitized, resulting in long-term synaptic changes in cortical receptive fields that can result in exaggerated pain perception. This process of chronic afferent input causing increased sensitivity and lower pain thresholds, with the remodeling of the central nociceptive pathways and receptors termed central sensitization. The consequence may be:
Substances Released When Tissue is Injured
The inflammatory cascade can sensitize peripheral nociceptors. Substances released include vasoactive peptides such as calcitonin, gene-related protein, neurokinin A, substance P, and mediators such as bradykinin and epinephrine prostaglandin E2, and serotonin. The pain signal is modulated in both segmental and descending pathways by neurochemical mediators such as endorphins (enkephalin) and monoamines (norepinephrine, serotonin). These mediators are thought to increase, reduce, shorten sustain the perception and response to pain. They also mediate the benefits of CNS-active drugs such as antidepressants, antiseizure drugs, membrane stabilizers, and opioids that interact with neurochemicals and specific receptors that treat chronic pain.
Psychologic factors are important pain modulators. They affect how patients describe and react to pain; such as complaining, being irritable, grimacing, or being stoic. They may also generate neural output that modulates neurotransmission along pain pathways. The psychologic reaction to protracted pain interacts with central nervous system factors that may induce long-term changes in pain perception.
Pain Theories
Intensity Theory
The theory goes back to the Athenian philosopher Plato (c. 428 to 347 B.C.) who, in his work Timaeus, defined pain not as a unique experience, but as an 'emotion' that occurs when the stimulus is intense and lasting. Centuries later, we are aware that especially chronic pain represents a dynamic experience, profoundly changeable in a spatial-temporal manner. A series of experiments, conducted during the nineteenth century, sought to establish the scientific basis of the theory. Based on the tactile stimulation and impulses of other nature, such as electrical stimulations, these investigations provided important information concerning the threshold for tactile perceptions and on the role of the dorsal horn neurons in the transmission/processing of pain.[26]
Cartesian Dualistic Theory
The oldest explanation for why pain manifested in specific populations was rooted in religious beliefs. Throughout history, religious ideologies have had a substantial influence on people’s thoughts and actions. As a result, the majority of people believed that pain was the consequence of committing immoral acts. There was also a belief that the suffering they endured was the individual’s way to repent for these sins.[9] Although this belief remained popular up until the nineteenth century, this was not due to the lack of other available theories. One of the first alternative scientific pain theories was bravely introduced in 1644 by the French philosopher Renee Descartes (1596-1650). This theory has the name in current literature as the Cartesian dualism theory of pain.[10]
The dualism theory of pain hypothesized that pain was a mutually exclusive phenomenon. Pain could be a result of physical injury or psychological injury. However, the two types of injury did not influence each other. At no point were they to combine and create a synergistic effect on pain, hence making pain a mutually exclusive entity.[11] In an attempt to placate the church, Descartes also included in his theory the idea that pain has a connection to the soul. He claimed that his research uncovered that the soul of pain was in the pineal gland, consequentially designating the brain as the moderator of painful sensations.[12]
The dualistic approach to pain theory fails to account for many factors that are known to contribute to pain today. Furthermore, it lacks explanation as to why no two chronic pain patients have the same experience with pain even if they had similar injuries. Despite these shortcomings, it still provided future researchers with a solid foundation to continue expanding the scientific understanding of the intricate phenomenon of pain.
Specificity Theory
Many scientists continued to do research long after Descartes proposed the dualistic theory of pain. However, it wasn’t until 1811 that another well-known pain theory came onto the scene. This theory, initially presented by Charles Bell (1774–1842), is referred to as the specificity theory. This theory is similar to Descartes' dualistic approach to pain in the way that it delineates different types of sensations to different pathways. In addition to the identification of specific pathways for different sensory inputs, Bell also postulated that the brain was not the homogenous object that Descartes believed it was, but instead a complex structure with various components.[13]
Scientists and philosophers alike spent the next century and a half further developing the specificity theory. One of the many contributors to this theory was Johannes Muller. In the mid-1800s, Muller published in Manual of Physiology that individual sensations resulted from specific energy experienced at certain receptors. Furthermore, Muller believed that there was an infinite number of receptors in the skin. This surplus of receptors accounted for the ability of an individual to discriminate between different sensations.[14] In 1894, Maximillian von Frey made another critical addition to the specificity theory that served to advance the concept: four separate somatosensory modalities found throughout the body. These sensations include cold, pain, heat, and touch.[15]
This concept correlates well with previous research done regarding this theory of pain, which served to reiterate the presence of distinct pathways for different sensations. Although this theory and the research surrounding it provided significant advancement to understanding pain, it still fails to account for factors other than those of physical nature that results in the sensation of pain. Much like the dualistic approach to pain, this theory also lacks an explanation for why sometimes pain persists long after the healing of the initial injury. This incomplete nature of the specificity theory regarding pain etiology necessitated additional theories and continued research.
Pattern Theory
Following the specificity theory, there were a handful of other philosophies introduced regarding the sensation of pain. Of these philosophies, the pattern theory of pain has the greatest coverage in the scientific literature. The American psychologist John Paul Nafe (1888-1970) presented this theory in 1929. The ideas contained with the pattern theory were directly opposite of the ideas suggested in the Specificity theory in regards to sensation. Nafe indicated that there are not separate receptors for each of the four sensory modalities. Instead, he suggested that each sensation relays a specific pattern or sequence of signals to the brain. The brain then takes this pattern and deciphers it. Depending on which pattern the brain reads, correlates with the sensation felt.[16] At the time of its introduction, the pattern theory gained significant popularity among many researchers. However, through further research and the discovery of unique receptors for each type of sensation, it can be stated with certainty that this theory is an inaccurate explanation for how we feel pain.
Gate Control Theory
In 1965, Patrick David Wall (1925–2001) and Ronald Melzack announced the first theory that viewed pain through a mind-body perspective. This theory became known as the gate control theory.[17] Melzack and Wall’s new theory partially supported both of the two previous theories of pain but also presented more knowledge to advance the understanding of pain further. The gate control theory of pain states that when a stimulus gets sent to the brain, it must first travel to three locations within the spinal cord. These include the cells within the substantia gelatinosa in the dorsal horn, the fibers in the dorsal column, and the transmission cells located in the dorsal horn.[18] The substantia gelatinosa of the spinal cord's dorsal horn serves to modulate the signals that get through, acting similar to a “gate” for information traveling to the brain.[19]
The sensation of pain that an individual feels is the result of the complex interaction among these three components of the spinal cord. Simply stated, when the “gate” closes, the brain does not receive the information that is coming from the periphery to the spinal cord. However, when the signal traveling to the spinal cord reaches a certain level of intensity, the “gate” opens. Once the gate is open, the signal can travel to the brain where it is processed, and the individual proceeds to feel pain. The information mentioned above accounts for the physical component of pain. Still, as stated earlier, the Gate Control Theory was one of the first to acknowledge that psychological factors contributed to pain as well. In their original study, Melzack and Wall suggested that in addition to the control provided by the substantia gelatinosa, there was an additional control mechanism located in cortical regions of the brain.[20]
In more recent times, researchers have postulated that these cortical control centers are responsible for the effects of cognitive and emotional factors on the pain experienced. Current research has also suggested that a negative state-of-mind serves to amplify the intensity of the signals sent to the brain as well.[21] For example, somebody who is depressed has a “gate” that is open more often, allowing more signals to get through, increasing the probability that an individual will experience pain from an otherwise normal stimulus. Also, there are reports that certain unhealthy lifestyle choices will also result in an “open gate,” which in turn leads to pain that is disproportionate to the stimulus.[22]
The gate control theory has proven to be one of the most significant contributions to the study of pain throughout history. The concepts that Melzack and Wall introduced to the study of pain are still utilized by researchers today. Even though this theory initiated the idea that pain wasn’t solely a result of physical injury but rather a complex experience, influenced by cognitive and emotional factors, additional research was necessary to comprehend the mechanisms and etiology of pain completely. This need precipitated the introduction of the following two philosophies regarding pain.
Neuromatrix Model
Almost thirty years after introducing the gate control theory of pain, Ronald Melzack introduced another model that contributed to the explanation of how and why people feel pain. Until the mid-1900s, most pain theories implied that this experience was exclusively due to an injury that had occurred somewhere in the body. The thinking was that if an individual suffered an injury, whether it be through trauma, infection, or disease, a signal would transmit to the brain, which would, in turn, result in the sensation of pain. Although Melzack had contributed to these previous theories, his exposure to amputees experiencing phantom limb pain in well-healed areas prompted his inquiry into this more accurate philosophy of pain. The theory he proposed is known as the neuromatrix model of pain. This philosophy suggests that it is the central nervous system that is responsible for eliciting painful sensations rather than the periphery.[23]
The neuromatrix model denotes that there are four components within the central nervous system responsible for creating pain. The four components are the “body-self neuromatrix, the cyclic processing, and synthesis of signals, the sentinel neural hub, and the activation of the neuromatrix.”[24] According to Melzack, the neuromatrix consists of multiple areas within the central nervous system that contribute to the signal, which allows for the feeling of pain. These areas include the spinal cord, brain stem and thalamus, limbic system, insular cortex, somatosensory cortex, motor cortex, and prefrontal cortex.[25] The signal that these areas of the central nervous system work together to create is responsible for allowing an individual to feel pain, and he referred to as the “neurosignature.” Furthermore, this theory states that input coming in from the periphery can initiate or influence the neurosignature, but these peripheral signals cannot create a neurosignature of their own.[26]
This idea that peripheral signals can alter the neurosignature is an important concept when considering the effect of nonphysical factors on an individual’s experience with pain. Melzack’s theory claimed that not only are there specific neurosignatures that elicit certain sensations but when there is an alteration in a certain signal, this allows for memory formation of these particular experiences. If the same circumstances occur again in the future, this memory allows for the same sensation to be felt.[27] In addition to the hypothesis that pain was a product of different patterns of signals from the central nervous system, the neuromatrix model continued to elaborate on the idea that was initially brought forward in the gate control theory, that pain can be affected not only by physical factors but by cognitive and emotional factors. Melzack suggested that hyperactivity of the stress response has a direct effect on pain. Hyperactivity of the stress response is when an individual exposed to increased levels of stress experiences a higher level of pain.[28]
Taking all of these claims into consideration, it is evident that pain is a complex issue that cannot be accounted for by physical factors alone. Even though the neuromatrix model further established the idea that cognitive and emotional factors influence pain in addition to physical factors, it still fails to account for social constructs of pain. Therefore, a new theory of pain must be utilized to appropriately explain the mechanism behind pain and why each individual’s experience with pain is unique.
Biopsychosocial Model
The biopsychosocial model provides the most comprehensive explanation behind the etiology of pain. This specific theory of pain hypothesizes that pain is the result of complex interactions between biological, psychological, and sociological factors. Any theory that fails to include all of these three pain constructs fails to provide an accurate explanation for why an individual is experiencing pain.[29] Although the term biopsychosocial was not introduced until 1954 by Roy Grinker (1900-1993), a neurologist and psychologist, many physicians had considered the utility of using such a model to approach the management of a patient’s pain long before this.[30]
One of the most prominent physicians who utilized this more comprehensive approach to pain was John Joseph Bonica (1917-1994). This Sicilian American anesthesiologist at Madigan Army Hospital established himself as the founding father of the pain medicine discipline. In the 1940s, Bonica cared for many patients who had returned home from World War II and were now experiencing debilitating pain due to injuries they had suffered in the war. He had recognized that the pain these wounded soldiers were experiencing was rather complex and not easily managed. This situation led him to propose that to adequately manage these patients, physicians needed to create interprofessional pain clinics comprising multiple disciplines.[31] At this moment in history, there was little support for the idea that pain was more than just the result of an injury, and Bonica was relatively unsuccessful in establishing these clinics. It wasn’t until 1977 that the biopsychosocial model was scientifically suggested as an explanation for the etiology of some medical conditions. George Engle claimed that to treat disease adequately; one must consider multidimensional concepts and manage the whole patient instead of focusing on a single issue.[32]
This methodology takes into account that the human body cannot be divided into separate categories when considering treatment options. Instead, it is beneficial to acknowledge the fact that illness and disease are the results of complex interactions between biological, psychological, and sociological factors, and they all affect an individual’s physical and mental well-being.[33] Although Bonica had technically been the first physician to comprehend the importance of using a biopsychosocial approach to pain, John D. Loeser, another anesthesiologist, has been credited as the first person to use this model in association with pain.[34]
Loeser suggested that four elements need to be taken into consideration when evaluating a patient with pain. These elements include nociception, pain, suffering, and pain behaviors. Nociception is the signal that is sent to the brain from the periphery to alert the body that there is some degree of injury or tissue damage. On the other hand, pain is the subjective experience that occurs after the brain has processed the nociceptive input. The last two components of pain that merit consideration is suffering and pain behaviors. The thinking is that suffering is an individual’s emotional response to the nociceptive signals and that pain behaviors are the actions that people carry out in response to the experience of pain. Both of these can be either conscious or subconscious.[35]
Loeser’s four pain elements account for the biological, psychological, and sociological factors that can create or influence an individual’s experience with pain. Failing to consider any one of these four elements when determining the cause or establishing a management plan could be a consideration as inadequate assessment or care. With a better understanding of what is causing a patient to experience pain, the doctor is provided with a more accurate foundation to begin formulating a treatment plan. Loeser’s findings prove that the Biopsychosocial Model of pain offers the most comprehensive philosophy and provides the framework that is needed to start appropriate therapy to manage patients with chronic pain adequately.
Histopathology
Chronic pain and opioids generally do not cause any specific histopathology in and of themselves. However, there is a diversity of histopathologic changes that can occur in the presence of improper/recreational parenteral administration of opioids. There may be chronic tissue damage present due to the original assault.[6]
Toxicokinetics
Opioids have an extensive diversity of durations and intensities of effect. For example, alfentanil has a half-life of around 1.5 hours; whereas, methadone has a half-life of between 8 to 60 hours. Opioid uptake and effect can also vary by administration route, some examples being fentanyl patches or long-acting oral formulations of oxycodone and morphine. Some, such as diphenoxylate and loperamide, have almost no effect other than suppression of bowel motility. Opioids such as methadone can significantly prolong the QT interval. Opioids can sometimes precipitate serotonin syndrome, especially when given to patients already taking various psychoactive medications (antidepressant medications like SSRI). There is an evolving body of knowledge that the intensity and quality of response to opioids can vary significantly between patients, which can be unrelated to tolerance; this is likely related to genetics, but this is not well characterized at this time.[30][26]
History and Physical
History
History should include the onset of pain, description, mechanism of injury if applicable, location, radiation of pain, quality, severity, factors contributing to relief or worsening of the pain, frequency of the pain, and any breakthrough pain. A verbal numeric rating scale (VNRS) or number scale for pain is a common measure to determine the severity of pain, numbered from 0 to 10. This tool is commonly used for pain intensity. Furthermore, associated symptoms should be assessed, such as muscle spasms or aches, temperature changes, restrictions to range of motion, morning stiffness, weakness, changes in muscle strength, changes in sensation, and hair, skin, or nail changes.
In addition to the patient's symptoms, the significance of the impact of the pain in day-to-day function should be discussed, and a review of daily living activities. It is important to understand how chronic pain affects the patient’s quality of life. Is pain impacting relationships or hobbies? Does the patient find themselves becoming depressed? Is the patient able to sleep throughout the night or exercise regularly? Can the patient go to work without limitations? Are activities of daily living affected, such as toileting, dressing, bathing, walking, or eating limited or restricted?
Older adults are a specific population that often identifies as suffering from chronic pain. The self-reporting of pain can be difficult in this population. Self-reporting of pain is essential for identifying and treating pain, while the inability to describe or communicate pain leads to undertreatment. Often elderly patients describe pain differently than the average population complicating diagnosis.[31][18] Instead of pain, an elderly patient may complain of soreness or discomfort.[32]
There are multiple acronyms used to obtain the history of a patient's pain. Some of the most commonly used abbreviations are "COLDERAS" and "OLDCARTS. These acronyms summarize the character, onset, location, duration exacerbating symptoms, relieving symptoms, radiation of pain, associated symptoms, and severity of illness. "PQRST" stands for provocation or palliation, quality, radiation or region, severity, and timing.[33]
A multidimensional assessment of a patient's pain and the severity of their pain can be completed. A Pain, Enjoyment, General Activity (PEG) tool can aid the multidimensional assessment of patients in pain.[34] The PEG score focuses on function and quality of life. A chronic pain patient who experiences daily 7/10 pain is treated with both pharmacological and nonpharmacological therapies. Following treatment, their pain is 5/10. A few points might not seem like a significant difference, but if their enjoyment and quality of life and function are improving, treatment may have had a profound impact on the patient's life. The PEG tool is scored 0 to 10 for each category. The higher the score, the worse the function and uncontrolled pain.
The Four-item Patient Health Questionnaire or PHQ-4 is a combination of the PHQ9 and GAD7 assessment tools used to evaluate depression and anxiety, respectively.[35] The PHQ-4 should be used as a screening tool for all cases of chronic pain. If the score of the PHQ-4 is more significant than five, then a full GAD-7, PHQ-9, and the Primary Care PTSD screening tools are recommended.[36]
The Defense and Veterans Pain Rating Scale (DVRPS) is a five-item tool with a 0 to 10 out pain scale, as well as an assessment of the impact of pain on sleep, mood, stress, and activity levels.[37]
In children's self-reporting, behavioral observation scales are used to assess pain.[38] Age-based rating scales of pain can be used. Visual analogs are also often implemented. Typically visual analogs are done with pictures of faces in various degrees of distress. By adolescence, children usually can rate their pain on a numerical scale, similar to adults.[39]
The Pediatric Pain Questionnaire and the Adolescent and Pediatric Pain Tool are used to assess the location of a patient's pain as well. The patient is asked to draw on the body map where they feel pain.[40] The ideal age for these tools is age 10 years.
Observational pain assessment tools are used in populations who cannot self-report. The facial expression, fussiness, distractibility, ability to be consoled, verbal responsiveness, and motor control are observational findings used in such an assessment tool. Observational pain assessment in infants or young children can use the (r-FLACC) tool.[38][41] The tool is an acronym for Revised Face, Legs, Activity, Cry, Consolability.[42][43] Multiple other validated tools can be used; the one that is better than another is the NAPI tool. However, multiple tools have been used and are validated.[44][45][46][41]
Nonverbal children with neurologic impairment (NI) is a challenging population to assess pain. Caregivers are often needed to help determine changes in the patient's behavior. Grimacing, moaning, increased muscle tone, crying, arching, atypical behavior such as aggressive behavior are a few symptoms to monitor in this population. Nonverbal children with NI include the Revised Face, Legs, Activity, Cry, Consolability (r-FLACC) scale, and the Individualized Numeric Rating Scale (INRS). The assessment adds specific behavior for atypical presentations.[42][45]
The Brief Pain Inventory (BPI) can be used to assess patients' beliefs on pain and the impact of pain on their lives.[47][48] Separately, the McGill Pain Questionnaire (SF-MPQ-2) includes a drawing for the location of pain on the human body, a questionnaire regarding previous pain medication use, and past experiences with pain.[49] Neuropathic pain is assessable using the Neuropathic Pain Scale to follow responses to therapy.
Physical
A detailed physical, including musculoskeletal, neurologic, and psychiatric exam, should be completed, as well as a focused examination of the area of pain.
Evaluation
Overview Of Safe Prescribing Assessment Guidelines
Health professionals are trained to prescribe pain medications; unfortunately, controlled substances are commonly misused. The following provides an overview of the requirements for the safe prescribing of controlled substances. A more detailed discussion follows.
Chronic Pain Assessment
Standard blood work and imaging are not indicated for chronic pain, but the clinician can order it when specific causes of pain are suspected. This can be on a case-by-case basis. In some cases, urine toxicology is ordered to monitor compliance and exclude nonprescription drugs.
Psychiatric disorders can amplify pain signaling making symptoms of pain worse.[50] Furthermore, comorbid psychiatric disorders, such as major depressive disorder, can significantly delay the diagnosis of pain disorders.[51] Major depressive disorder and generalized anxiety disorder are the most common comorbid conditions related to chronic pain. There are twice as many prescriptions for opioids prescribed each year to patients with underlying pain and a comorbid psychiatric disorder compared to patients without such comorbidity.[32] Intuitively, this makes sense. For example, a patient suffering from depression often complain of fatigue, sleep changes, loss of appetite, and decreased activity. These symptoms can make their pain worse over time. It is also crucial to realize patients with chronic pain are at an increased risk for suicide and suicidal ideation.[19][20]
Simultaneously screening for depression is recommended for patients with chronic pain. The Minnesota Multiphasic Personality Inventory-II (MMPI-2) or Beck's Depression Scale are the two most commonly used tools. The MMPI-2 has been used more frequently for patients with chronic pain.[52][53]
Addiction Risk Assessment
[9]
[54]
[55]
The clinician should consider information from the history and physical, family members, the state prescription monitoring program, and screening tools to assess the risk of developing an untoward behavioral response to opioids. Patients can be stratified to three risk levels:
Low-risk: standard monitoring, vigilance, and care
Objective signs and symptoms, localizable physical pathology
Confirmatory testing such as physical exam findings, CT, MRI, etc.
No individual or family history of substance abuse
At most, mild medical or psychologic comorbidity
Age < 45
High pain tolerance
Active coping strategies
Willingness to participate in multimodal therapy
Attempting to function at normal levels
Moderate-risk: additional level of monitoring and more frequent provider contact
Significant pain
Defined pathology with objective signs and symptoms
Confirmatory testing such as physical exam findings, CT, MRI, etc.
Moderate psychologic problems controlled by therapy
Moderate comorbidities well controlled by medical therapy and are not affected by opioids
Mild opioid tolerance but not hyperalgesia without addiction or physical dependence
Individual or family history of substance abuse
Pain involving more than three regions of the body
Moderate levels of pain acceptance
Active coping strategies
Willing to participate in multimodal therapy
Attempting to function at normal levels
High-risk: intensive and structured monitoring, frequent follow-up contact, consultation with addiction psychiatrist, and limited monthly prescription of short-acting opioids
Significant widespread pain
No objective signs and symptoms
Pain involves more than 3 body regions
Divergent drug-related behavior
Individual or family history of addiction, dependency, diversion, hyperalgesia, substance abuse, or tolerance
Major psychologic problems
Age >45
HIV-related pain
High levels of pain exacerbation
Poor coping strategies
Unwilling to participate in multimodal therapy
Not functioning at a normal lifestyle
Prescribing Opioids
Before prescribing opioids, complete a detailed patient history that includes:
Indication requested for pain relief
Location, nature, and intensity of pain
Prior pain treatments and response
Comorbid conditions
Potential physical and psychologic pain impact on the function
Family support, employment, and housing
Leisure activities, mood, sleep, substance use, and work
Emotional, physical, or sexual abuse
When considering opioids, weigh the risks of abuse, addiction, adverse drug reactions, overdose, and physical dependence. If there are any special concerns, such as a history of substance abuse, consult a psychiatrist or addiction specialist. If current substance abuse, withhold prescribing until the patient is involved in an addiction treatment and monitoring program.
Assessment Tools
[55]
Screening tools help determine the risk level and degree of monitoring and structure required for a treatment plan; however, their validity is not yet supported in the literature. Some examples of opioid tools include:
Brief Intervention Tool
Brief Intervention Tool is a 26-item "yes-no" questionnaire used to identify signs of opioid addiction or abuse. The items assess for problems related to drug use-related functional impairment.
CAGE, CAGE-AID, and CAGE-Opioid
CAGE (Cut down, Annoyed, Guilty, and Eye-opener) Questionnaire consists of four questions designed to assess alcohol abuse. CAGE-AID and CAGE-OPIOID are revised versions to assess the likelihood of current substance abuse.[56]
Current Opioid Misuse Measure (COMM)
The Current Opioid Misuse Measure is a 17-item patient self-report assessment designed to identify abuse in chronic pain patients. It identifies aberrant behaviors associated with opioid misuse in patients already receiving long-term opioid therapy.
Diagnosis, Intractability, Risk, and Efficacy (DIRE) Tool
The Diagnosis, Intractability, Risk, and Efficacy is a clinician-rated questionnaire used to predict patient compliance with long-term opioid therapy. Patients scoring low are poor candidates for long-term opioids.
Mental Health Screening Tool
The Mental Health Screening Tool is a five-item screen that evaluates feelings of calmness, depression, happiness, peacefulness, and nervousness in the past month. A low is an indicator that the patient should be referred to a pain management specialist.
Opioid Risk Tool
The Opioid Risk Tool is a five-item assessment to evaluate for aberrant drug-related behavior. It categorizes the patient into low, medium, or high levels of risk for aberrant drug-related behaviors based on question responses concerning previous alcohol, drug abuse, psychologic disorders, and other risk factors.
Pain Assessment and Documentation Tool (PADT)
Guidelines by the CDC, the Federation of State Medical Boards, and Joint Commission stress documentation from both a quality and medicolegal perspective. The Pain Assessment and Documentation Tool (PADT) was designed to help the clinician document appropriate information.
Screener and Opioid Assessment for Patients with Pain-Revised (SOAPP-R)
The Screener and Opioid Assessment for Patients with Pain-Revised (SOAPP-R) is a screen with questions addressing the history of alcohol or substance use, cravings, mood psychologic status, and stress. The SOAPP-R helps assess the risk level of aberrant drug-related behaviors and the monitoring level needed.
VIGIL
Verification: Is this a responsible opioid user?
Identification: Is the identity of this patient verifiable?
Generalization: Do we agree on mutual responsibilities and expectations?
Interpretation: Do I feel comfortable allowing this person to have controlled substances?
Legalization: Am I acting legally and responsibly?
Urine Drug Tests (UDT)
Urine drug tests evaluate the use of the medication prescribed and detect unsanctioned drug use. The CDC recommends drug testing before starting opioid therapy and at least annually.
One study suggests monitoring frequency based on risk level.[57]
Testing is usually done with class-specific immunoassay drug panels; however, this may be followed with gas chromatography/mass spectrometry for specific metabolite detection. The test should identify the specific drug. If urine test results suggest aberrant opioid use, discuss the issue in a positive, supportive approach, and document the discussion.
Treatment / Management
Overview Of Safe Treatment With or Without Controlled Substances
Generally, the provider should consider the use of a non-controlled substance to alleviate pain. However, if this fails, and the decision is made to prescribe a controlled substance, before beginning therapy, two important documents should be obtained:
Informed consent - should include the drug prescribed, risks (overdose, respiratory depression, dependence, drug interaction, death, and if the female risk of neonatal withdrawal syndrome), benefits (pain relief), desired goal or outcome, expected length, and follow-up care. Those goals should be collaborative.
Patient-provider agreement - signed by the patient and provider and includes responsibilities of the patient and provider, goals of controlled substance use, and the consequences of noncompliance with the treatment plan.
The first prescription is a trial with a determined follow-up appointment
Includes pill counts if needed
Refills and how they are handled
Use of a single provider for all controlled substances
Exit strategy when goals are achieved
Mild pain - start with acetaminophen or non-steroidal anti-inflammatory drug, or in some cases both. Whenever possible, consider alternative pain relief therapies, including physical therapy, massage, electrotherapy stimulation, Yoga, biofeedback, and acupuncture.
Moderate pain - start with a mild opioid such as codeine or tramadol. Also, consider supplemental alternative pain relief therapies.
Severe pain - start with a stronger opioid such as hydrocodone, hydromorphone, oxycodone, or morphine. Use immediate-release controlled substances with a half-life of 2-4 hours until the dose is stabilized. Adjust dose initially every 2-3 days. Extended-release or long-acting opioids with a half-life of 8-12 hours in the same family are added later. Also, consider supplemental alternative pain relief therapies.
Chronic Pain
Healthcare professionals who treat patients with chronic pain should understand best practices in opioid prescribing, approaches to pain assessment, pain management modalities, and appropriate use of opioids for pain control. Pharmacologic and nonpharmacologic approaches should be evaluated. Patients with moderate-to-severe chronic pain who have been assessed and treated with non-opioid therapy without adequate pain relief are candidates for opioid therapy. Initial treatment should be a trial of therapy, not a definitive course of treatment. The CDC has issued updated guidance on the prescription of opioids for chronic pain. These guidelines address when to initiate or continue opioids for chronic pain; opioid selection, dosage, duration, follow-up, and discontinuation; and assessing risk and addressing opioid use harm.
Pain Referral
Recommendations are to refer a patient to pain management in the case of debilitating pain, which is unresponsive to initial therapy. The pain may be located at multiple locations, requiring multimodal treatment or increases in dosages for adequate pain control or invasive procedures to control pain. Treatment of both pain and a comorbid psychiatric disorder leads to a more significant reduction of both pain and symptoms of the psychiatric disorder.[58] Pain may also worsen concurrent depression; thus, the treatment of pain has been demonstrated to improve the responses to the treatments for depression.[59] There are multiple pharmacological, adjunct, nonpharmacological, and interventional treatments for chronic, severe, and persistent pain.
Pharmacologic Options
The list of pharmacological options for chronic pain is extensive. This list includes nonopioid analgesics such as nonsteroidal anti-inflammatories (NSAIDs), acetaminophen, and aspirin. Additionally, medications such as tramadol, opioids, antiepileptic drugs (gabapentin or pregabalin) can be useful. Furthermore, antidepressants such as tricyclic antidepressants and SNRI’s, topical analgesics, muscle relaxers, N-methyl-d-aspartate (NMDA) receptor antagonists, and alpha 2 adrenergic agonists are also possible pharmacological therapies.
Treatment response can differ between individuals, but treatment is typically done in a stepwise fashion to reduce the duration and dosage of opioid analgesics. However, there is no singular approach appropriate for the treatment of pain in all patients.[60]
Major Pain Types And Treatment Options
Musculoskeletal
Chronic musculoskeletal pain is nociceptive pain. The treatment of such pain is in a stepwise approach but includes a combination of nonopioid analgesics, opioids, and nonpharmacological therapies. First-line therapy would be acetaminophen or NSAIDs. Both are effective for osteoarthritis and chronic back pain.[61][62][63] However, NSAIDs are relatively contraindicated in patients with a history of heart disease or myocardial infarction, renal disease, or patients on anticoagulation or with a history of ulcers.[64][65] There is limited evidence of which NSAID to use over another. One nonsteroidal antiinflammatory pharmacological agent may have a limited effect on a patient's pain, while another may provide adequate pain relief. The recommendations are to try different agents before moving on to opioid analgesics.[66] Failure to achieve appropriate pain relief with either acetaminophen or NSAIDs can lead to considering opioid analgesic treatment.
Opioids are considered a second-line option; however, they may be warranted for pain management for patients with severe persistent pain or neuropathic pain secondary to malignancy.[67] There have been conflicting results on the use of opioids in neuropathic pain. However, for both short term and intermediate use, opioids are often used to treat neuropathic pain.[68] Opioid therapy should only start with extreme caution for patients with chronic musculoskeletal pain.[69] Side effects of opioids are significant and frequent and may include opioid-induced hyperalgesia, constipation, dependence, and sedation. For chronic musculoskeletal pain, they are not superior to nonopioid analgesics.[70][71]
Administration of opioid analgesics should be reserved for when alternative pain medications have not provided adequate pain relief or contraindicated and when pain is impacting the patient's quality of life. The potential benefits outweigh the short and long-term effects of opioid therapy. The patient must make an informed choice before starting opioid treatment after discussing the risks, benefits, and alternatives to opioids.[70][72][73] Patients taking opioids at greater than 100 morphine milligram equivalents per day are at significantly increased risk of side effects. Side effects of opioids such as respiratory compromise will increase as the dosages increase. Patients with chronic pain could benefit from a therapy program designed to wean them from opioid analgesics to a safer dosage.[74][75] Long-acting opioids should only be used over short-acting opioids in the setting of disabling pain, causing severe impairment to quality of life.[76]
There is an estimated 78 percent risk of an adverse reaction to opioids such as constipation or nausea, while there is a 7.5 percent risk of developing a severe adverse reaction ranging from immunosuppression to respiratory depression.[77] Patients with chronic pain who meet the criteria for the diagnosis of opioid use disorder should receive the option of buprenorphine to treat their chronic pain. Buprenorphine is a considerably better alternative for patients with very high daily morphine equivalents who have failed to achieve adequate analgesia.
Different types of pain also warrant different treatments. For example, chronic musculoskeletal back pain would be treated differently from severe diabetic neuropathy. A combination of multiple pharmacological therapies is often necessary to treat neuropathic pain. Less than 50% of patients with neuropathic pain will achieve adequate pain relief with a single agent.[78] Adjunctive topical therapy, such as lidocaine or capsaicin cream, can be utilized as well.[79][80]
Neuropathic
The initial treatment of neuropathic is often with gabapentin or pregabalin. These are calcium channel alpha 2-delta ligands. They are indicated for postherpetic neuralgia, diabetic neuropathy, and mixed neuropathy.[81] There is limited evidence in the use of other antiepileptic medications to treat chronic pain, where many of these, such as lamotrigine, have a more significant side effect profile. The exception is carbamazepine in the treatment of trigeminal neuralgia and other types of chronic neuropathic pain.[82][83]
Alternatively, antidepressants such as dual reuptake inhibitors of serotonin and norepinephrine (SNRI) or tricyclic antidepressants (TCA) can is an option. Antidepressants are beneficial in the treatment of neuropathic pain, central pain syndromes, and chronic musculoskeletal pain. For neuropathic pain, antidepressants have demonstrated a 50 percent reduction of pain. Fifty percent is a significant reduction, considering the average decrease in pain from various pain treatments is 30%.[84][85]
The serotonin-norepinephrine reuptake inhibitor (SNRI) duloxetine is a useful treatment for treating chronic pain, osteoarthritis, and the treatment of fibromyalgia.[86] Furthermore, the efficacy of duloxetine in the treatment of comorbid depression is comparable to other antidepressants.[87][84] Venlafaxine is an effective treatment for neuropathic pain, as well.[88] A TCA can also be utilized, such as nortriptyline. TCA medications may require six to eight weeks to achieve their desired effect.[67]
Adjunctive topical agents such as topical lidocaine are a useful treatment for neuropathic pain and allodynia as in postherpetic neuralgia.[89][90] Topical NSAIDs have been shown to improve acute musculoskeletal pain, such as a strain, but are less effective in chronic pain. Yet, topical NSAIDs are more effective than controls in the treatment of pain related to knee osteoarthritis.[91][92] Separately, topical capsaicin cream is an option for chronic neuropathic or musculoskeletal pain unresponsive to other treatments.[93] Botulinum toxin has also demonstrated effectiveness in the treatment of postherpetic neuralgia.[94] The use of cannabis is also an area of interest in pain research. There is some evidence that medical marijuana can effectively treat neuropathic pain, while the evidence is currently limited in treating other types of chronic pain.[95]
Additional Nonpharmacologic Options
The list of nonpharmacological therapies for chronic pain is extensive. Nonpharmacological options include heat and cold therapy, cognitive behavioral therapy, relaxation therapy, biofeedback, group counseling, ultrasound stimulation, acupuncture, aerobic exercise, chiropractic, physical therapy, osteopathic manipulative medicine, occupational therapy, and TENS units. Interventional techniques can also be utilized in the treatment of chronic pain. Spinal cord stimulation, epidural steroid injections, radiofrequency nerve ablations, botulinum toxin injections, nerve blocks, trigger point injections, and intrathecal pain pumps are some of the procedures and techniques commonly used to combat chronic pain. TENS units' efficacy has been variable, and the results of TENS units for chronic pain management are inconclusive.[96] Deep brain stimulation is for post-stroke and facial pain as well as severe, intractable pain where other treatments have failed.[97] There is limited evidence of interventional approaches to pain management. For refractory pain, implantable intrathecal delivery systems are an option for patients who have exhausted all other options. Cognitive-behavioral has been found to be particular helpful for pelvic pain syndromes.[98]
Spinal cord stimulators are an option for patients with chronic pain who have failed other conservative approaches. Most commonly, spinal cord stimulators are placed following failed back surgery but can also be an option for other causes of chronic pain such as complex regional pain syndrome, painful peripheral vascular disease, intractable angina, painful diabetic neuropathy, and visceral abdominal and perineal pain.[99][100][101][102][103] Spinal cord stimulators have shown a 50% reduction of pain compared to continued medical therapy.[104]
Differential Diagnosis
Pain is a symptom, not a diagnosis. Developing a differential diagnosis for a patient's chronic pain is based on assessing the possible underlying etiologies of the patient's pain. It is essential to determine what underlying injury or disease processes are responsible for the patient's pain since this requires the identification of effective treatment. For instance, it is crucial to determine if a patient's neuropathic pain is peripheral or central. In another example, if a patient suffers from severe knee pain, it is essential to consider whether or not the knee pain is secondary to severe osteoarthritis since the patient may benefit from an injection or possibly from a knee replacement. In contrast, if the knee pain were instead related to a different condition such as rheumatoid arthritis, infection, gout, pseudogout, or meniscal injury, very different treatments would be necessary.
The differential diagnosis for generalized chronic pain would include patients who develop allodynia from chronic opioids as well as patients suffering from a major depressive disorder and other psychiatric or sleep disorders, including insomnia. Furthermore, autoimmune diseases such as lupus or psoriatic arthritis, fibromyalgia, and central pain syndromes should be considered in states involving wide-spread, generalized chronic pain states. The four main categories of pain are neuropathic, musculoskeletal, mechanical, and inflammatory. Persistent and under-treated painful conditions can lead to chronic pain. Thus chronic pain is often a symptom of one or multiple diagnoses and can become its diagnosis as it becomes persistent and the body's neurochemistry changes. It is critical to treat acute and subacute pain before chronic pain develops.
Treatment Planning
Opioid therapy should begin as a trial for a pre-defined period, usually less than 30 days. Treatment goals should be established prior to the initiation of opioid therapy. These include the level of relief of pain, anxiety, depression, the return of function while avoiding unnecessary opioid use. The plan should include therapy selection, progress measures, and additional consultations, evaluations, referrals, and therapies. The provider should:
Start at the lowest possible dose and then titrate to effect
Start with short-acting opioid formulations
Discuss the need for frequent risk/benefit assessments
Be instructed in the signs and symptoms of respiratory depression
Reassess risk/benefit with each dose increase
Decisions to titrate dose to 90 mg or more morphine equivalent dose should be justified
Be knowledgeable of federal and state opioid prescribing regulations
Be knowledgeable of patient monitoring, equianalgesic dosing, and cross-tolerance with opioid conversion
Augment treatment with nonopioid or, if necessary immediate-release opioids over long-acting opioids
Taper opioid dose whenever possible
Consent and Treatment
[9]
The opioid prescription should include documented informed consent and a treatment agreement addressing:
Drug interactions
Physical dependence
Side effects
Tolerance
Physical dependence
Driving and motor skill impairment
Limited evidence of long-term benefit
Addiction, dependence, misuse
Risk/benefit profile of the drug prescribed
Signs/symptoms of overdose
Prescribing policies should be clearly described, including policies regarding the number and frequency of refills and procedures for lost or stolen medications.
Patient and Physician Treatment Agreement
The patient should agree to use medications safely, avoid "doctor shopping," and to consent to urine drug testing
The prescriber should agree to address problems, followup visits, and scheduled refills
Reasons for opioid therapy change or discontinuation should be listed. Agreements can also include follow-up visits, monitoring, and safe storage and disposal of unused drugs. If the patient does not speak English, an interpreter should be used.
Discontinuing Opioid Therapy
Discontinuing opioid therapy should be based on a physician-patient discussion. Opioids should be discontinued when the pain has resolved, side effects develop, analgesia is inadequate, or quality of life is not improved, deteriorating function, or there is evidence of aberrant medication use. Opioids should be tapered slowly, and an addiction specialist should manage withdrawal.
Toxicity and Adverse Effect Management
Adverse Reactions to Opioids
Common adverse reactions include drowsiness, respiratory depression, confusion, dizziness, nausea/vomiting, headache, fatigue, pruritus, pinpoint pupils, constipation, and urinary retention. Because opioids induce euphoria at higher doses than prescribed, these drugs are at high risk for abuse and addiction. Long term drug tolerance, hyperalgesia, or increased sensitivity to pain caused by damage to nociceptors or peripheral nerves may occur.
Depressants
Hypnotics, sedatives, and tranquilizers treat anxiety and sleep disorders. These drugs increase the inhibitory activity of the neurotransmitter gamma-aminobutyric acid by inhibiting overall brain activity, producing a calming effect. Examples of depressants include:
Anxiety
Benzodiazepines are schedule IV medications and include drugs such as alprazolam, clonazepam, diazepam, estazolam, and triazolam. They are used to treat anxiety, stress reactions, muscle spasms, and sleep disorders. They should be used short-term with caution as they have a high risk of addiction, dependence, and tolerance. The combination of benzodiazepines and opioids should be avoided due to the potential for addiction and respiratory depression.
All CNS depressants can cause confusion, drowsiness, and poor coordination. Avoid stopping these medications abruptly due to the risk of dangerous or fatal withdrawal symptoms or seizures. Benzodiazepine overdose is treated with a benzodiazepine antagonist, flumazenil, which can be administered via IV and provides rapid reversal.
For anxiety treatment, there are options that are less risky such as buspirone, which binds to serotonin and dopamine D2 receptors. It causes minimal drowsiness and has less abuse potential.
Sleep
Whenever possible, prescribers should select non-benzodiazepine sleep medications such as eszopiclone, zolpidem, and zaleplon, which act on GABA type A receptors in the brain but with fewer side effects and less risk of dependence, and they are schedule IV. Other options include melatonin and ramelteon.
Stimulants
Stimulants often abused include dextroamphetamine, methamphetamine, and methylphenidate. They work by enhancing the effects of the neurotransmitters norepinephrine and dopamine in the brain. While stimulants increase alertness, cognition, energy, and motivation, they also induce vascular constriction resulting in elevated heart rate and blood pressure, increased respiratory rate, dilated airway, elevated blood glucose, and insomnia. They are used to treat attention-deficit hyperactivity disorder, narcolepsy, and rarely depression. Misuse can cause euphoria as a result of increased dopamine activity in the brain. Abrupt withdrawal can cause depression, fatigue, and insomnia. Abuse or overdose may cause hostility, paranoia, psychosis, hyperthermia, arrhythmias, cardiovascular arrest, or seizures. They are classified as schedule II drugs.
A slightly safer alternative is modafinil, which works to block the reuptake of dopamine. It has a slightly safer profile and is classified as schedule IV.
The American Society of Interventional Pain Physicians guidelines recommends monitoring opioid adherence, abuse, and noncompliance through urine drug tests and monitoring programs.
The treatment plan for opioid use in chronic pain should include frequent assessment of pain level, origin, and function. If there is a change of dosage or agent, the frequency of patient visits should be increased. Chronic response to opioids should be monitored by evaluating the 5 A's.
Signs and symptoms, if present, that suggests treatment goals are not being achieved include:
Decreased appetite
Excessive sleeping or day/night reversal
Impaired function
Inability to concentrate
Mood volatility
Lack of involvement with others
Lack of re-engaging in life
Lack of hygiene
The decision to change, continue, or terminate opioid therapy is based on achieving treatment objectives without adverse effects. Physicians, wherever possible, should work with pharmacists.
Acute Overdose Management
[26]
Accidental or deliberate overdose is always a risk factor in patients taking opioids. The patient and family should be instructed in the signs and symptoms of an overdose and basic emergency management until paramedics' arrival.
The immediate response to overdose management is to secure the airway and breathing; however, survival is heavily dependent upon the rapid administration of an opioid antagonist. Many states allow naloxone distribution to the public. Licensed healthcare providers may prescribe opioid antagonists for at-risk individuals, relatives, or caregivers. Emergency medical service personnel, peace officers, and firefighters also have the drug available.
While opioid antagonists such as naloxone, naltrexone, and nalmefene are available, acute overdoses are usually treated with naloxone as it quickly reverses opioid-related respiratory depression. Naloxone competes with opioids at receptor sites in the brain stem, reversing desensitization to carbon dioxide and preventing respiratory failure.
The naloxone dose is 0.4 to 2 mg administered intravenously, intramuscularly, or subcutaneously. The dose may be repeated every 2 to 3 minutes. Naloxone is available in pre-filled auto-injection devices. Advanced Cardiac Life Support protocols should be continued while naloxone is being administered.
Prognosis
Current chronic pain treatments can result in an estimated 30% decrease in a patient's pain scores.[60] A thirty percent reduction in a patient's pain can significantly improve patients' function and quality of life.[105] However, the long-term prognosis for patients with chronic pain demonstrates reduced function and quality of life. Improved outcomes are possible in patients with chronic pain improves with the treatment of comorbid psychiatric illness. Chronic pain increases patient morbidity and mortality, as well as increases rates of chronic disease and obesity. Patients with chronic pain are also at a significantly increased risk for suicide compared to the regular population.
Spinal cord stimulation results in inadequate pain relief in about 50% of patients. Tolerance can also occur in up to 20 to 40 percent of patients. The effectiveness of spinal cord stimulation decreases over time.[106] Similarly, patients who develop chronic pain and are dependent on opioids often build tolerance over time. As the amount of morphine milligram equivalents increases, the patient's morbidity and mortality also increase.
Ultimately, prevention is critical in the treatment of chronic pain. If acute and subacute pain receives appropriate treatment, and chronic pain can be avoided, the patient will have limited impacts on their quality of life.
Complications
Chronic pain leads to significantly decreased quality of life, reduced productivity, lost wages, worsening of chronic disease, and psychiatric disorders such as depression, anxiety, and substance abuse disorders. Patients with chronic pain are also at a significantly increased risk for suicide and suicidal ideation.
Many medications often used to treat chronic pain have potential risks and side effects and possible complications associated with their use.
Acetaminophen is a standard pharmacological therapy for patients with chronic pain. It is taken either as a single agent or in combination with an opioid. The hepatotoxicity occurs with acetaminophen when exceeding four grams per day.[107] It is the most common cause of acute liver failure in the United States.[108] Furthermore, hepatotoxicity can occur at therapeutic doses for patients with chronic liver disease.[109]
Frequently used adjunct medications such as gabapentin or pregabalin can cause sedation, swelling, mood changes, confusion, and respiratory depression in older patients who require additional analgesics.[110] These agents require caution in elderly patients with painful diabetic neuropathy. Also, gabapentin or pregabalin, combined with opioid analgesics, has been shown to increase the rate of patient mortality.[111]
Duloxetine can cause mood changes, headaches, nausea, and other possible side effects and should be avoided in patients with a history of kidney or liver disease.
Feared complications of opioid therapy include addiction as well as overdose resulting in respiratory compromise. However, opioid-induced hyperalgesia is also a significant concern. Patients become more sensitive to painful stimuli while on chronic opioids.[112] The long-term risks and side effects of opioids include constipation, tolerance, dependence, nausea, dyspepsia, arrhythmia (methadone treatment QT prolongation), and opioid-induced endocrine dysfunction, which can result in amenorrhea, impotence, gynecomastia, and decreased energy and libido. Also, there appears to be a dose-dependent risk of opioid overdose with increasing daily milligram morphine equivalents.
Complication rates for spinal could stimulators are high, ranging from five up to 40%.[113][114] Most commonly, lead migration occurs, causing inadequate pain relief, often requiring revision and anchoring.[115][116] Lead movement often occurs in the cervical region of the spinal cord, given an increased range of motion of the cervical vertebra.[117][118] Spinal cord stimulator lead fracture can occur in up to 9% of placements.[119][120] Seromas are also very common and may require surgical incision and drainage.[121][113] The risk of infection following a spinal cord stimulator placement is between 2.5 and 12 percent.[122][123] Lastly, direct spinal cord trauma could occur. The most significant infectious complication would be a spinal cord abscess. A dural puncture can cause a post-dural headache in up to 70% of patients.[124][125][121] The most significant adverse to spinal cord stimulator placement would be a spinal epidural hematoma. This emergency would require immediate neurosurgical decompression of the hematoma. The incidence of a spinal epidural hematoma is 0.71%.[126]
Drug Diversion and Drug Seeking
[54]
Unfortunately, due to addiction or financial gain, some individuals seek prescribed opioids for illicit purposes. Prescription opioids may be obtained from a friend or relative, purchased from a black market drug dealer, obtained by doctor shopping and acquiring drugs from multiple prescribers, and theft from clinics, hospitals, or pharmacies.
Aggressive demands for more opioids
Asking for opioids by name
Behaviors suggesting opioid use disorder
Forged prescriptions
Increased alcohol use
Increasing medication dose without provider permission
Injecting oral medications
Obtaining medications from nonmedical sources
Obtaining opioids from multiple providers
Prescription loss or theft
Reluctance to decrease opioid dosing
Resisting medication change
Requesting early refills
Selling prescriptions
Sharing or borrowing similar medications
Stockpiling medications
Unsanctioned dose escalation
Using illegal drugs
Using pain medications to treat other symptoms
Drug Diversion Interventions
Prescribers and dispensers can take several precautions to avoid drug diversion. Some approaches include:
Communication among providers and pharmacies to avoid "doctor shopping"
Educate patients on the dangers of sharing opioids
Encourage patients to keep opioid medications in a private place
Encourage patients to refrain from public disclosure of opioid use
Report patient prescribing to state central database if available
If a patient is suspected of drug-seeking or diversion, consider the following actions:
Inquire about prescription and illicit drug use
Obtain a urine drug screen
Perform a thorough examination
Perform pill counting
Prescribe smaller quantities of the opioid
If a patient is abusing prescribed opioids, this is a violation of the treatment agreement. The provider may then chose to discharge the patient from their practice. If the relationship is terminated, the provider must do it legally. The provider should avoid patient abandonment, ending a relationship with a patient without consideration of continuity of care, and without providing notice to the patient. To avoid abandonment charges, the patient must be given enough advanced warning to allow them to secure another physician and facilitate the transfer of care.
Patients with a substance abuse problem or addiction should be referred to a pain specialist. Theft or loss of controlled substances should be reported to the Drug Enforcement Administration. If drug diversion has occurred, the activity should be documented and reported to law enforcement.
Consultations
Seek consultation or patient referral when input from a pain specialist, addiction specialist, or psychiatrist is needed, particularly for long-term chronic pain management. Clinicians who prescribe opioids should be aware of opioid addiction treatment options.
Deterrence and Patient Education
Involvement of Patient and Family
The patient and family can assist in making informed decision-making regarding continuing or discontinuing opioid therapy. Family members are often aware of when a patient is depressed and less functional. Questions to ask the family include:
Is the patient's day focused on taking opioid pain medication?
What is the frequency of pain medication?
Does the patient have any other alcohol or drug problems?
Does the patient avoid activity?
Is the patient depressed?
Is the patient able to function?
What To Teach A Patient Taking Opioids
Avoid driving or operating power equipment
Avoid stoping opioids suddenly
Avoid taking other drugs that depress the respiratory system as alcohol, sedatives, and anxiolytics
Contact prescribing if pain medication is not adequate for relief
Destroy opioids based on product-specific disposal information (usually flushing down the toilet or mixing with cat litter or coffee grounds)
Do not chew tables
Do not share opioids with friends or family
Follow prescribed dosing regimen
Provide product-specific information
Take opioids only as prescribed
Pearls and Other Issues
Maintain Accurate Medical Records Regarding Opiate Prescriptions
All clinicians should maintain accurate, complete, and current medical records, including:
All communication should be noted
Notes should be clear documenting dose adjustments, effectiveness, and any adverse effects
Describe adherence or lack of adherence to treatment
Urine drug screen results
Concerning behaviors
Family interactions
In particular, document any decisions regarding the termination of care
Federal and State Laws
[127]
Several regulations and programs at the federal and state levels reduce prescription opioid abuse, diversion, and overdose. These laws require:
Immunity from prosecution for individuals seeking assistance during an overdose
Pain clinic oversight
Patient identification prior to dispencing
A physical examination prior to prescribing opioids
Prescription limits
A prohibition from obtaining controlled substance prescriptions
Tamper-resistant prescriptions
Federal Laws
The U.S. Drug Enforcement Administration (DEA) sets national standards for controlled substances. Drug scheduling was mandated under The Federal Comprehensive Drug Abuse Prevention and Control Act of 1970. The law addresses controlled substances within Title II. The DEA maintains a list of controlled medications and illicit substances categorized from scheduled I to V. The five categories have their basis on the medication’s proper and beneficial medical use and the medication’s potential for dependency and abuse. The purpose of the law is to provide government oversight over the manufacturing and distribution of these types of substances. Prescribers and dispensers are required to have a DEA license to supply these drugs. The licensing provides links to users, prescribers, and distributors.[128][129][130]
The schedules range from Schedule I to V. Schedule I drugs are considered to have the highest risk of abuse, while Schedule V drugs have the lowest potential for abuse. Other factors considered by the DEA include pharmacological effect, evidenced-based knowledge of the drug, risk to public health, trends in the use of the drug, and whether or not the drug has the potential to be made more dangerous with minor chemical modifications.
"High abuse potential with no accepted medical use; medications within this schedule may not be prescribed, dispensed, or administered" Examples include marijuana (cannabis), heroin, mescaline (peyote), lysergic acid diethylamide (more...)
It is essential to understand the DEA controlled-substance scheduling both to ensure adequate caution when prescribing medications with high abuse potential and also to ensure against prescribing outside of one's authority.[131][132]
The Controlled Substances Act has great potential to improve patient safety by providing federal oversight for drugs with a high potential for abuse. Providers of scheduled substances (physicians, dentists, podiatrists, advanced practitioners) may have links to the distribution of these substances. They are required to have a DEA license and record prescription of scheduled drugs. This licensing prevents overprescribing and obligates providers to be wary of potential drug-seeking patients. The dispenser must also be aware of a patient's medication history and be mindful of the potential for polypharmacy if a patient seeks multiple providers. The current opioid epidemic is a time where federal oversight and interdisciplinary coordination can potentially reduce harm to patients prescribed scheduled drugs drastically. However, it will take further time and evaluation to know if drug scheduling actually reduces abuse, addiction, and overdose.[133][134][135][136][137]
Florida Law on Controlled Substance Prescribing
Most states, including Florida, have specific laws regarding the prescription of controlled substances. Each provider should become familiar with the key provisions.
HB 21
Florida Prescription Drug Monitoring Program (PDMP) provides changes regarding database reporting, checking, and access to information. The new law requires a prescriber or dispenser or their designee to consult the PDMP database dispensing history before prescribing a controlled substance to anyone 16 years old or older. Any dispensing of a controlled substance must be reported to the database by the close of the next business day.
A nonopioid controlled substance listed in Schedule V is exempt from mandatory checking. However, if it does contain any amount of an opioid, then the prescriber or dispenser has to consult the database prior to prescribing or dispensing.
If the PDMP database cannot be accessed, the practitioner can prescribe or dispense the controlled substance but must document the reason the database was not consulted and must limit the prescription to a three-day supply.
If a dispenser dispenses controlled substances but has no dispensing transactions in the preceding seven (7)-day period, the dispenser must report this information to E-FORCSE by filing a zero report described in the Dispenser’s Implementation Guide: https://flmd.us/dig.
Practitioners authorized to prescribe or dispense controlled substances may look up, view, and print controlled substance dispensing information on their specific patients. Prescribers should take these rules seriously. If a prescriber fails to consult the database prior to subscribing, they are subject to a DOH non-disciplinary citation. Continued offenses may result in disciple from their specialties medical board. Willful and knowing failure to report is a first-degree misdemeanor.Remember, the 3-7 day limit on prescribing Schedule II opioids applies to acute pain – not chronic nonmalignant pain. However, the requirement for checking the PDMP database applies to the prescription of virtually any controlled substance for any reason.
Section 456.44 – Controlled Substance Prescribing
This law covers both the management of acute and chronic pain in the State of Florida.
Controlled Substance Prescriptions
Written on counterfeit-proof prescription blank ordered from DOH vendor found at http://www.floridaheatlh.gov/licensing-and-regulation
Drug quantity must be written both textually and numerically
Dated
Signed by the prescriber; it may be issued electronically
Dispensing Controlled Substances
Prescription Drug Monitoring Program (PDMPP)
Acute Pain
Definition - The normal, predicted, physiological, and time-limited response to an adverse chemical, thermal, or mechanical stimulus associated with surgery, trauma, or acute illness.
The definition does not include pain-related to:
Cancer
Terminal Condition - progressive disease or medical or surgical condition that causes significant functional impairment, is not considered by a treating physician to be reversible without the administration of life-sustaining procedures and will result in death within one year after diagnosis if the condition runs its normal course
Palliative Care - to provide relief of symptoms related to an incurable, progressive illness or injury
Traumatic Injury - with an Injury Severity Score of 9 or greater
3-day Pain Management
7-day Pain Management
Chronic Nonmalignant Pain - [S. 456.44]
Prescribing physician, ARNP, or PA of any Schedule II-IV controlled substances for chronic nonmalignant pain must:
Definition Chronic Malignant Pain [456.44(1)(e)] - Pain unrelated to cancer that persists beyond the usual course of the disease or the injury that is the cause of the pain or more than 90 days after surgery.
Standards
Complete and Document H & P Examination Before Treatment
Nature of pain
Intensity
Prior and current treatment
Comorbid conditions
Effect of pain physical and psychological function
Review of PMH and prior studies
Document the history of alcohol and substance abuse
Document 1 or more medical indications for the use of a controlled substance
Document written plan assessing the risk of aberrant drug-related behavior and monitoring
Includes objectives for determining the success of treatment
Includes any further diagnostic evaluations or treatments
Includes drug therapy adjustments and interdisciplinary care
Includes risks of abuse, addiction, and dependence
Document a controlled substance written agreement sign by the patient
Frequency and number of controlled substances and refills
Compliance and reasons for discontinuation
Agreement controlled substances shall ONLY be prescribed by one treating physician
Includes informed consent regarding aspects of care, expectations of behavior, and defining consequences
Describes the tapering plan when treatment ends
Establishes follow-up intervals not to exceed 3 months assessing:
Etiology of pain
Treatment efficacy
Continued need
Progress
Adverse effects
Compliance
If any history of substance abuse, the patient must be referred to an addiction medicine specialist or psychiatrist
Accurate, Complete, and Current Records
Photocopy of government-issued ID
H & P including a history of drug abuse or dependence
Test results
Evaluations and consultations
Discussion of risks and benefits
Medication type, dosage, quantity, and date prescribed
Periodic treatment review
Agreements and instructions
Drug test results
Copies of all prescriptions
Prescriber name legibly written
Refer patients with signs or symptoms of substance abuse to an addiction or pain specialist and follow recommendations for ongoing care
456.44 Does not apply to:
Board-certified or eligible anesthesiologists, neurologists, physiatrists, or rheumatologists
Board-certified surgeons with privileges at a hospital or surgical center that primarily provide surgical services
Board-certified or eligible pain specialists
Physicians who are AOA, ABMS, or ABMP board-certified or eligible who regularly performs interventional pain procedures
Physicians who prescribe controlled substances to inpatients
Pain Management Clinics
Registration – Pain management clinics must register with the Florida Department of Health.
All facilities that (1) advertise in any medium for any type of pain management services, or (2) where, in any month, a majority of patients are prescribed opioids, barbiturates, benzodiazepines, or carisoprodol for the treatment of chronic nonmalignant pain.
Registration Exceptions - The following entities are exempted from the registration requirement:
A clinic licensed as a facility pursuant to chapter 395
A clinic in which the majority of the physicians provide surgical services
A clinic owned by a publicly held corporation whose total assets exceed $50 million
A clinic affiliated with an accredited medical school
A clinic that does not prescribe controlled substances for the treatment of pain
A clinic owned by a corporate entity exempt from federal taxation under 26 U.S.C. s. 501(c)(3)
A clinic wholly owned and operated by a board-eligible or board-certified anesthesiologists, physiatrists, rheumatologists, or neurologists
The clinic is wholly owned and operated by a physician multispecialty practice where one or more board-eligible or board-certified medical specialists have also completed fellowships in pain medicine approved by the Accreditation Council for Graduate Medical Education, or who are also board-certified in pain medicine by the American Board of Pain Medicine or a board approved by the American Board of Medical Specialties, the American Association of Physician Specialists, or the American Osteopathic Association, to perform interventional pain procedures of the type routinely billed using surgical codes
Summary of Electronic Florida Online Reporting Of Controlled Substances Requirements
The Florida PDMP facilitates collecting, analyzing, and reporting information on controlled substances prescribing and dispensing.
All prescribers must consult the Electronic Florida Online Reporting of Controlled Substances Evaluation (E-FORCSE) and review a patient's controlled substance dispensing history before prescribing or dispensing a controlled substance to a patient 16 years of age or older
E-FORCSE must be consulted, and a report made for new and existing patients and should be done each time a controlled substance is prescribed or dispensed.
If E-FORCSE cannot be accessed due to a temporary technologic or electrical failure, the prescription may be issued (with documentation of the exception) but should be limited to a 3-day supply.
All clinicians who dispense controlled substances must report the prescription to E-FORCSE as soon as possible, but no later than the close of the next business day.
Reporting is waived for:a. Dispensing of a controlled substance in the healthcare system of the Department of Correctionsb. Dispensing of a controlled substance to a person younger than 16 years of age
Controlled Substance Prescribing Continuing Education
Prescribers authorized to prescribe controlled substances must take a board-approved two-hour continuing education course on prescribing controlled substances.
The course must be taken from “a statewide professional association of physicians in this state that is accredited to provide educational activities designated for the AMA PRA Category 1 credit™ or the American Osteopathic Category 1-A continuing medical education credit as part of biennial license renewal”.
The course must be taken by allopathic physicians, osteopathic physicians, podiatrists, dentists, and optometrists who are registered with the DEA.
Advanced registered nurse practitioners and physician assistants must take a three-hour course on controlled substance prescribing.
Each physician is required to take the course with an initial license and then prior to each subsequent license renewal
APRN/PA Controlled Substance Prescribing Standards
7-day maximum of Schedule II
PA and ARNP prohibited from prescribing controlled substances in a pain management clinic
ARNP prohibited from prescribing controlled substance psychiatric medication to children unless they are a psychiatric NP
PA prohibited form prescribing controlled substances psychiatric medications to children
PAs and ARNP must complete 3 hours of CE on effective and safe controlled substance prescribing
Enhancing Healthcare Team Outcomes
Chronic pain is a significant condition that affects many millions of people and is an important public health concern with considerable morbidity and mortality and associated opiate drug diversion and misuse. Thus chronic pain is best managed with an interprofessional approach. Managing chronic pain requires an interprofessional team of healthcare professionals, including a primary care physician, nursing team, pharmacist, and pain medicine specialists. Without proper management, the patient's quality of life can have a deleterious impact. The evaluation and treatment of such patients are paramount, but health professionals must work as a team to avoid drug diversion and misuse.
Chronic pain correlates with several severe complications, including severe depression and suicide attempts and ideation. The lifetime prevalence for chronic pain patients attempting suicide attempt was shown to be between 5% and 14%; suicidal ideation was approximately 20%.[19] These complications often require psychiatric intervention and advanced pharmacological or interventional therapies. Severe symptoms must receive treatment immediately, leading to an increase in healthcare costs. It is of the utmost importance to identify the risk factors and perform a thorough assessment of the patient with chronic pain as well as monitor for progression of symptoms. A team approach is an ideal way to limit the effects of chronic pain and its complications.
Evaluation of a patient with acute pain by the primary care provider to prevent the progression of chronic pain is the recommended first step.
Conservative management of chronic pain should commence when symptoms are mild or moderate, including physical therapy, cognitive-behavioral therapy, and pharmacological management.
A pharmacist or other expert knowledgeable in the medications frequently utilized to treat chronic pain should evaluate the medication regimen to include medication reconciliation to preclude any drug-drug interactions and alert the healthcare team regarding any concerns.
The patient should follow up with a primary care provider and pain specialists as necessary regularly to assess and effectively treat the patient's pain.
Clinicians must address comorbid psychiatric disorders. This action may require the involvement of a psychiatrist, depending on the severity of the patient's symptoms.
If symptoms worsen on follow up or if there is a concerning escalation of pharmacological therapy such as with opioids, a referral to a pain medicine specialist merits consideration.
If the patient has exhausted various pharmacological and nonpharmacological treatment options, interventional procedures can be a consideration.
If the patient expresses concern for suicidal ideation or plan at any time, an emergent psychiatric team should evaluate the patient immediately.
Patients who have developed opioid dependence secondary to pharmacological therapy should be offered treatment, possibly referral for addiction treatment or detoxification if indicated. The patient should be put on a medication weaning schedule or possibly medications to treat opioid dependence.
Based on CDC recommendations, patients on high-dose opioid medications or patients with risk factors for opioid overdose (e.g., obesity, sleep apnea, concurrent benzodiazepine use, etc.) should receive naloxone at home for the emergent treatment of an unintentional overdose.
The interprofessional team should openly discuss and communicate clearly about the management of each patient so that the patient receives optimal care delivery. This area is where nurses and pharmacists can play a crucial role by verifying patient compliance with the treatment plan and monitoring for progress (or lack of) with the present treatment plan. Nurses and pharmacists can help monitor for adverse medication side effects, concerns regarding diversion or misuse of opioids, and communicate any areas of concern to the treating clinicians. Effective, open interprofessional communication is crucial in the optimal management of chronic pain [Level 2] and minimizing the negative effects of chronic pain in the patient.
Interprofessional Team Case Study
CC: Syncope and Confusion
HPI: A 70-year-old confused female arrives in the trauma after she was found passed on the bathroom floor near the toilet. The husband reports a past history of morbid obesity, diabetes, kidney disease, and chronic right hip pain, for which she has been scheduled for prosthetic hip surgery replacement that has been delayed to get her weight under control. She has been prescribed a combination of hydrocodone and acetaminophen to allow control of the pain enough for ambulation and daily pool exercises. Lately, the pain has been getting worse, and the husband mentions that occasionally she takes more medicine than prescribed.
PE: Vital signs T 98.7 degrees F, Bp 100/70, HR 110, RR 14, and O2 Saturation 92%.
Physical exam reveals a somnolent and female that arouses to a painful stimulus. The heart, lung, and extremity exam is normal. There are no focal neurologic deficits.
Work-up
Laboratory studies including a CBC, chemistry, and urinalysis are normal except for a moderate elevation of the blood urea nitrogen and creatinine. A chest x-ray and pelvic film are negative for fracture. The ECG was normal. The drug screen is positive for opioids and cannabinoids.
The patient is given naloxone and becomes awake and conversant. She admits that she was sitting on the toilet urinating, and the last thing she remembers is feeling faint. She indicates that she has difficulty sleeping and walking due to chronic hip pain, and she has severe pain with exercise in their home pool. She denies suicidal ideation. She admits to taking an extra pain pill and “smoking a joint” prior to the episode.
Checking E-FORCE reveals she has been on a three times a day dose of her oxycodone and acetaminophen for the last six weeks prescribed by her orthopedic surgeon.
Treatment
The patient is admitted to the hospital, and orthopedic surgery, pain management, pharmacy, physical therapy, and dietician are consulted. Subsequent workup by the interprofessional team concludes the incident was caused by an accidental overdose of her opioid medication combined with her comorbid conditions.
The family and husband were informed that due to age, diabetes, and kidney disease, the opioid she is taking was cleared less efficiently. With the doubling of her dose, she developed an acute toxic encephalopathy. The family and patient have a limited understanding of the potential side effects of opioids in treating pain, a poor understanding of exercise, and dieting for weight control.The interprofessional team recommends to the family continuing opioids at the prescribed dose without any additional doses, rare NSAIDs for breakthrough pain, monitored physical therapy and exercise, a planned diet, temporary placement of a TENS unit, pain monitored by a pain specialist, and surgical intervention as soon as possible.
At discharge, a written treatment and management plan is presented to the family and patient for discussion and consent. The goals include relief of pain, increased exercise and weight loss, and surgical intervention as soon as possible.
The patient is scheduled for outpatient pain management, physical therapy, and weight management. Before discharge, the pharmacist counsels the family and patient regarding the safe use, dosage regulation, side effects, and proper disposal of opioid medication. An emergency naloxone kit is prescribed, and the family is educated on its use.
Follow-up
Three months after discharge, the patient has successfully lost 40 pounds (18 kg) and was cleared for surgery. Following hip replacement, the patient's pain has dramatically diminished, and she is gradually tapered off of her pain medications. She continues to maintain regular exercise and dieting until she is noticeably improved. She reports that she feels better, is enjoying life, and is encouraged by her progress.
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Disclosure: Alexander Dydyk declares no relevant financial relationships with ineligible companies.
Disclosure: Daniel Sizemore declares no relevant financial relationships with ineligible companies.
Disclosure: Kamron Fariba declares no relevant financial relationships with ineligible companies.
Disclosure: Devang Sanghavi declares no relevant financial relationships with ineligible companies.
Disclosure: Burdett Porter declares no relevant financial relationships with ineligible companies.
