Comorbid chronic pain and substance abuse: Guidelines for management

Pain management presents many challenges for the healthcare provider, but among the most challenging patients are those with histories or current problems with substance abuse or dependence. Observations that persons with an active substance abuse problem (for example, the IV drug abusing person with end-stage AIDS and severe painful peripheral neuropathy), or even more provocative, persons with a remote history of substance abuse, are discriminated against in terms of appropriate pain management, suggest that greater attention should be placed on this important problem. A number of factors represent barriers to effective management in this population, including a lack of knowledge on the part of clinicians, biases regarding issues of substance abuse and even the use of opiates in the management of pain, a paucity of research that can inform clinical decision-making, and an associated lack of clear guidelines for practice in this important arena. These barriers will be briefly discussed and a few guidelines for addressing this problem will be provided.

Any discussion of the issues related to the management of co-prevalent chronic pain and substance abuse requires a consideration of key definitions. For example, when referring to the use of drugs, addiction refers to a pattern of behaviors, most notably compulsive seeking of the drug or impaired judgment about the use of the drug, as well as other risk taking behaviors that can result in harm to the patient (e.g., loss of employment) and/or the patient’s family or social group. It is a behavioral phenomenon and is characterized by aberrant behaviors. Addiction does not refer to physiological dependence or tolerance. Identification of the addicted patient, either related to prescribed or illicit drugs, is particularly challenging, but critical to the effective management of pain. A few suggestions for reducing the likelihood of fostering the development of addiction to prescribed medications, and for managing pain in the substance abusing or dependent patient are described below. In most cases, establishing a collaboration with specialists in managing and treating the substance abusing or dependent patient, may be the most important step that a provider can take.

Physical dependence is defined by the presence of a characteristic withdrawal syndrome when use of the drug is abruptly discontinued. Withdrawal from opioids typically involves craving for the drug, nausea, vomiting, hypertension, tachycardia, diarrhea, and diaphoresis, among other symptoms. For obvious reasons, efforts to anticipate withdrawal and minimize its likelihood are critically important in the management of pain with opioids, or other medications for which dependence is an issue. Tolerance is a gradually developed, physiological phenomenon, characterized by the need for increasing amounts of the drug to have the same physiological, and behavioral effects. In the case of opioids, this means gradually increasing the dose of the medication in order to achieve a similar analgesic effect. A 20% increase in the dose of the opioid over an eight-week period is a good rule of thumb.

Pseudo-addiction is a particularly important construct in the context of pain management. It refers to behaviors exhibited by the patient that reflect under-treatment of pain. In this context, the patient may exhibit behaviors almost identical to those of the addict, that is, preoccupation with taking the medication and with obtaining and renewing prescriptions for the medication. Pseudo-addiction, of course, resolves with adequate management of the pain problem. Nevertheless, differentiation of addiction from pseudo-addiction is a central challenge for the provider.

Healthcare providers should become aware of their own biases in the use of analgesics that may interfere with the effective management of pain. An uninformed fear of fostering addiction is one bias that has been observed to be common among many providers. Interestingly, the prevalence of addiction to analgesic medications is observed to be low, and there is a growing consensus about strategies that can be employed to minimize this likelihood. Fear related to regulatory agencies such as the DEA is also common. Continuing education opportunities abound that include presentations by employees of the DEA that provide information about appropriate practice and reassurance about risk to providers when appropriate guidelines are followed.

More generally, several studies now document that providers readily acknowledge their lack of knowledge and skill in managing pain. Given the complexities of the field, generally speaking, and the particular problems associated with the management of chronic pain, providers should be encouraged to seek continuing education in this critically important area. Central to the education of providers is the development of knowledge and skill in conducting a comprehensive pain assessment that can foster the consideration of important individual differences, such as a history of substance abuse, in the development of an effective plan for pain care.

Beyond the general call for more education and training in this area, a few specific recommendations can be highlighted for the management of chronic pain in the patient with current or past substance abuse. Critically important is an appreciation of the growing literature that supports the use of medications other than opioids in the management of specific painful conditions (e.g., anti-imflammatories for arthritis, anticonvulsants and antidepressants for neuropathic pain). In addition, evidence is mounting to support the efficacy of multiple non-pharmacological approaches, including rehabilitation medicine and psychological approaches. In the setting of co-prevalent chronic pain and substance abuse, development of a plan for care that relies on non-pharmacological strategies is particularly indicated.

A few additional strategies are increasingly used to minimize problems with addiction when opioids are being prescribed. One particularly useful strategy is the use of an “opioid agreement”. This agreement outlines patient and provider responsibilities and contingencies, such as a requirement on the part of the patient to bring medication containers and unused medications to appointments and a requirement on the part of the provider to refill scripts in a timely manner when patient responsibilities have been met. A second strategy is the requirement of frequent brief visits to monitor adherence to the provider’s directions for use of the medication and to assess efficacy and side effects.

This strategy avoids the prescription of unnecessarily large quantities of medication that encourages abuse. Frequent visits also encourage the provider (and patient) to link use of the medication with an ongoing assessment of pain. Providers of opioids, especially when a history of abuse is documented and/or when abuse or diversion is suspected, are encouraged to require random toxicology screens. This requirement is usually made clear and provided to the patient in writing as part of the opioid agreement. Finally, especially when chronic opioid therapy is planned, long-acting and extended release preparations of the opioid may be indicated as an alternative to short-acting medications that are known to increase the likelihood of abuse and dependence.

Ultimately, it is incumbent on the provider to rely on a trusting and mutually respectful relationship with the patient when prescribing medications with a potential for abuse. Ongoing reassessment of the patient’s experience of pain and response to the medication is also critical for successful management of the complex patient with chronic pain and co-prevalent substance abuse.