Methadone in the chronic pain patient with a substance use disorder.

Methadone, used both to treat opioid addiction and to manage chronic pain, is commonly prescribed as an opioid of choice for patients with chronic pain and comorbid substance use disorders. This practice apparently derives from the belief that because methadone is widely used in opioid addiction treatment programs, it is an excellent choice for the management of chronic pain in individuals with substance use disorders. However, chronic pain and addiction treatment contexts are vastly different. In recent years, methadone-related morbidity and mortality have skyrocketed, driven largely by its use as an analgesic. Methadone is a uniquely complex opioid, responsible for a disproportionate percentage of opioid-related morbidity and mortality. Its use in high-risk patients should not be a reflexive choice. Rather, it should be employed only after careful consideration of relative risks and benefits.