Influence of acute bupropion pre-treatment on the effects of intranasal cocaine.

AIMS The aim of this experiment was to determine the influence of acute bupropion pre-treatment on subject-rated effects and choice of intranasal cocaine versus money. DESIGN A randomized, within-subject, placebo-controlled, double-blind experiment. SETTING An out-patient research unit. PARTICIPANTS Eight cocaine-using adults. MEASUREMENTS Subjects completed nine experimental sessions in which they were pre-treated with 0, 100 or 200 mg oral immediate release bupropion. Ninety minutes later they sampled an intranasal cocaine dose [4 (placebo), 15 or 45 mg] and made six choices between that dose and an alternative reinforcer (US$0.25), available on independent, concurrent progressive ratio schedules. Subjects also completed a battery of subject-rated, performance and physiological measures following the sample doses of cocaine. FINDINGS After 0 mg bupropion, the high dose of cocaine (45 mg) was chosen five of six times on average compared to 2.25 of six choices for placebo cocaine (4 mg) (P < 0.05). Active bupropion reduced choice of 45 mg cocaine to 3.13 (100 mg) or 4.00 (200 mg) out of six drug choices on average. Bupropion also consistently enhanced positive subject-rated effects of cocaine (e.g. good effects; willing to take again) while having no effects of its own. CONCLUSIONS The atypical antidepressant, bupropion, acutely appears to reduce preference for intranasal cocaine versus a small amount of money but to increase reported positive experiences of the drug.