Prescription Opioid Abuse Among Pain Patients: Predictors of Relapse

In this study, we will assess opioid self-administration in a laboratory setting in persons with pain who have a history of opioid abuse. Participants diagnosed with mild to moderate pain will be admitted to hospital for 7 weeks and transitioned from their baseline prescription opioid to a standing daily dose of Suboxone (buprenorphine/naloxone combination). During this maintenance period, participants will have the opportunity in a laboratory setting to self-administer oxycodone; subjective responses as well as analgesic, physiological and performance effects will be measured. In the second phase of this study, the same patients who participated in the inpatient phase will be followed on an outpatient basis while maintained on Suboxone for 12 weeks. . The hypotheses of this study are that (1) higher progressive ratio break-point values for oxycodone, higher subjective ratings of euphoria, and less pain relief will predict early relapse to opioid abuse; (2) the abuse liability measures will be more strongly correlated with relapse than the pain measures; (3) subjective ratings of euphoria will increase and of pain will decrease in an oxycodone dose-dependent manner (i.e. euphoria will increase and pain will decrease as dose increases); and (4) experimentally induced pain will decrease in an oxycodone dose-dependent manner.