Abuse liability of buprenorphine--a study among experienced drug users.

Six male post-detoxified opiate dependent subjects were evaluated for abuse liability of buprenorphine (0.6 mg), morphine (16 mg), pentazocine (30 mg) and distilled water (placebo) intramuscular injection in a single blind cross-over random order. Subjective states, drug discrimination, drug linking, sedation and euphoria were assessed at pre-injection, 30 min and 4 hrs post-injection. Buprenorphine caused significant euphoria and was identified as heroin. On all parameters, buprenorphine resembled morphine rather than pentazocine and placebo. The data suggest that abuse liability of buprenorphine is similar to morphine i.e. moderate rather than low.