Pain is very common in persons with a history of addiction, but few studies have examined the best treatment of pain in this population. This is a study to determine the pain relief provided by intravenous hydromorphone (Dilaudid) or buprenorphine given to persons maintained on stable doses of methadone or buprenorphine who have chronic musculoskeletal pain. Experimental sessions will require overnight stays on a residential research unit. In these sessions, persons will be exposed to standard experimental pain techniques at baseline and then rate the relief (if any) provided by the study medication when exposed to the same techniques. Persons will be asked to participate in 3 sessions, each separated by at least 7 days.

Inclusion Criteria:

Opioid dependence according to the Mini International Neuropsychiatric Interview (MINI) and verified by the PI; urine toxicology negative for drugs of abuse but positive for opioid maintenance agent; stable buprenorphine (12-16 mg) dose for the past 30 days; chronic musculoskeletal pain (>3 months) as documented in medical history and physical; able and willing to perform/tolerate pain procedures; able to communicate in English.

Exclusion Criteria:

Current illicit substance use at screening or during trial as verified by urine toxicology screen and/or self-report (including cannabis use); current alcohol dependence as assessed on the MINI); medical or psychiatric condition known to influence quantitative sensory testing (QST) (e.g. HIV, peripheral neuropathy, current Major Depressive Disorder, Schizophrenia, Raynaud's syndrome); use of prescribed or over the counter analgesic agents or psychotropic medications known to have analgesic properties for 24 hours prior to session; previous allergic reaction to hydromorphone or buprenorphine; women who are pregnant, lactating or planning to get pregnant during the course of the trial.