Self-administration of intravenous buprenorphine and the buprenorphine/naloxone combination by recently detoxified heroin abusers

Buprenorphine is a partial -opioid agonist and -opioid an-tagonist currently under development as a maintenance med-ication for heroin dependence. Because of concerns about illicit diversion of buprenorphine, a combination tablet containing buprenorphine and naloxone has been developed. The present study evaluated the reinforcing effects of intravenously admin-istered placebo, buprenorphine alone (BUP; 2 and 8 mg), and the buprenorphine/naloxone combination (BUP/NX; 2 mg of buprenorphine plus 0.5 mg of naloxone, and 8 mg of buprenor-phine plus 2 mg of naloxone) in recently detoxified heroin abusers during a 6-week inpatient study. Participants (n 6) were detoxified from heroin over approximately 1 week imme-diately after admission. During the next 5 weeks, the reinforcing effects of placebo, BUP, and BUP/NX were evaluated. Partic