Supplementing the antidepressant Wellbutrin (bupropion) with a reward system called “contingency management” (CM) can further reduce cocaine use in addicted subjects maintained with methadone, new research shows.

With CM, an addicted individual is given a positive reinforcement whenever he provides objective proof of a positive behavioral change. In the present study, subjects were given a small amount of money for each cocaine-free urine sample they provided. The amount could escalate to a maximum of $45 per week.

In the 25-week study, which is reported in the Archives of General Psychiatry, 106 opiate-dependent, cocaine-abusing individuals were randomly allocated to one of four treatments: CM plus Wellbutrin, CM plus placebo, voucher control plus Wellbutrin, and voucher control plus placebo.

With the voucher control, subjects simply received money for each urine sample submitted, regardless of the result.

Opiate use fell significantly and to a similar extent in all four groups during the study, the report indicates.

In the CM plus Wellbutrin group, cocaine-positive samples dropped significantly during the first 13 weeks and then remained low during the following 12 weeks. After an initial rise in cocaine use, a drop in use was also noted in the CM plus placebo group, albeit not to the extent seen in the CM plus Wellbutrin group.

By contrast, no reduction in cocaine use was seen in either voucher control group.

This study, the authors conclude, indicates that Wellbutrin augmented with CM “may be an effective treatment for cocaine abuse.”

SOURCE: Archives of General Psychiatry February 2006.