Chronic noncancer pain (CNCP) is a leading cause of disability and discomfort for patients in the United States. Health care expenses for chronic back pain alone were roughly billion in 2005. Opioids have long been an accepted treatment for the pain associated with cancer or the end of life, and the past few decades have seen an increase in the use of opioids for chronic noncancer pain as well, although opioids in this setting remain controversial. The American Academy of Pain Medicine and American Pain Society recently gathered a multidisciplinary expert panel to formulate evidence-based guidelines on chronic opioid therapy (COT) for adults with CNCP (J. Pain 2009;10:113-30). These guidelines were devised to be applicable to both primary care and specialty centers, and to have as their goal the promotion of a “balanced approach” that recognizes the importance of addressing both pain control and improvement in functional status for patients, while at the same time developing procedures to protect against the increasing public health problem of prescription drug abuse.
One of the most important aspects of initiating COT is proper patient selection. A thorough history and physical examination—as well as appropriate diagnostic tests to evaluate the patient's pain—should be completed. Clinicians should consider if the underlying condition causing pain can be treated with nonopioid therapy before deciding to start COT. Randomized trials demonstrating the benefit of COT are seen with patients who have moderate to severe pain that is unrelieved by nonopioid therapy. COT is effective for both neuropathic and nonneuropathic pain, and can be considered if the patient's functioning or quality of life is significantly affected and if benefits of therapy outweigh potential risks. It is important for patients to have reasonable expectations upon starting COT: Total pain relief is rare, and most patients' pain improves 2-3 points on a 0- to 10-point scale. One of the most significant risks associated with opioid therapy is drug abuse or misuse. The strongest predictor of drug abuse or misuse in COT is a personal or family history of drug or alcohol abuse.
After the patient receives informed consent regarding the risks and benefits of COT, the physician should consider a written management plan. This plan can include the goals of therapy, random urine drug screens, instructions for dispensing medications, follow-up timeline, consequences for misuse of medications, and clarification that opioids should be obtained from only one prescriber.
There is no evidence that any one opioid is better for initiating therapy. It may be safer to begin with short-acting opioids for initial therapy because they have a shorter half-life and possibly less risk of accidental overdose; however, there is insufficient evidence to recommend short-acting vs. long-acting opioids. The suggested benefits of long-acting opioids include more consistent control of pain, improved compliance, and lower risk of addiction or abuse. For breakthrough pain, short-acting or rapid-onset opioids used as needed may be effective. There is limited evidence at this time to recommend any specific opioid in this setting.
Methadone use has increased over the last decade, but clinicians need to be aware that it has complicated pharmacokinetics and should be used by clinicians familiar with its use and risks.
Patients on COT should be monitored periodically to assess level of function, pain severity, adverse events, compliance with drug regimens, and degree of progress to goals of therapy. Clinicians can obtain periodic urine drug screens in patients who are at high risk for drug abuse or misuse, and may consider such screening in low-risk patients. Patients with repeated dose titrations should be reassessed, especially for adverse effects and drug misuse. Opioid rotation may be considered for patients with intolerable adverse effects or those with inadequate pain control despite continued dose titration. Patients involved in aberrant drug-related behaviors should be weaned off COT. Therapy should also be tapered for patients who are experiencing intolerable adverse effects or who are not progressing to goals of therapy. Slower rates of weaning (for example, a 10% dose reduction per week) may help decrease symptoms of withdrawal.
When prescribing COT, clinicians should consider incorporating psychotherapeutic interventions for the treatment of CNCP.
When the benefits outweigh the risks, chronic opioid therapy is a reasonable and efficacious way to treat individuals with chronic noncancer pain. Patients should be selected carefully and monitored appropriately during treatment with chronic opioids.
An interdisciplinary approach, including psychotherapeutic interventions, may be beneficial for patients with chronic noncancer pain.
Dr. Skolnik is an associate director of the family medicine residency program at Abington (Pa.) Memorial Hospital.Dr. Menichello is an attending physician at Grand View Medical Practices at High Point in Chalfont, Pa
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