There are few published studies assessing the efficacy of pharmacologic treatments for attention-deficit hyperactivity disorder (ADHD) among substance abusers seeking treatment. Eleven patients who met DSM-IV diagnostic criteria for cocaine dependence and adult ADHD were entered into a 12-week single-blind trial of divided daily doses of bupropion (BPR). All patients received weekly individual standardized relapse prevention therapy. Treatment compliance and retention were good. Patients reported significant reductions in attention difficulties, hyperactivity and impulsivity. Self-reported cocaine use, cocaine craving, and cocaine positive toxicologies, also decreased significantly. In a previously published trial, 12 patients who met similar diagnostic criteria for adult ADHD and cocaine dependence were entered into a 12-week trial of divided daily doses of sustained-release methylphenidate (MPH). Improvements observed on BPR were similar to, and did not differ from those previously observed with MPH. These preliminary data suggest that BPR may be as effective as sustained-release MPH, when combined with relapse prevention therapy, for cocaine abusers with adult ADHD. However, a future study directly comparing BPR to MPH in a double-blind placebo-controlled trial is needed.