Substance misuse in patients who have comorbid chronic pain in a clinical population receiving methadone maintenance therapy for the treatment of opioid dependence.

•Opioid-dependent patients with chronic pain are more likely to misuse benzodiazepines.•Opioid-dependent patients with chronic pain are more likely to misuse cannabinoids.•Opioid-dependent patients with chronic pain are not more likely to misuse opioids.•This pattern of substance misuse is shown to persist in the longer term.