We used an open-labeled,21-day inpatient detoxification treatment to compare the short-term effects of a 10-day buprenorphine plus 19-day carbamazepine regimen (n=15) to a 14-day oxazepam plus 19-day carbamazepine regimen (n=12) during rapid detoxification from opioids and other abused drugs. Somatic and psychopathological changes were assessed using the following rating scales: ASI, HAMD, SCL-90-R, and SOWS. Eighteen of 27 patients (67%) completed the study. Four dropouts (27%) were treated with buprenorphine/carbamazepine (BPN/CBZ) and the other five dropouts (42%) were treated with oxazepam/carbamazepine (OXA/CBZ). Repeated measures analysis of variance showed that SOWS scores were significantly less pronounced with BPN-CBZ than with OXA/CBZ. On the first day of admission, no significant difference in HAMD scores was detected (BPN/CBZ11.6, BPN/CBZ 1.0). On day 14, HAMD was significantly less pronounced in BPN/CBZ (3.0) than in OXA/CBZ (6.1). BPN/CBZ showed a significant improvement in the ASI score on days 7 and 14 compared with OXA/CBZ. Three of nine items of the SCL-90-R showed a trend toward less pronounced outcome in BPN-CBZ. No severe side effects occurred during treatment in either group. The buprenorphine/carbamazepine regimen provided significantly more effective relief from affect disturbances and withdrawal syndromes than the oxazepam/carbamazepine regimen. The pharmacological basis of these effects of buprenorphine (kappa-antagonism activity, mu-agonism activity) are discussed.