The authors conducted an open-label trial of pemoline, a dopaminergic CNS stimulant, for the treatment of cocaine addiction in methadone-maintained patients. Ten patients who met DSM-III-R criteria for cocaine dependence participated in an eight-week study. Findings showed that 50% of patients were discontinued from the study due to complaints of side-effects. Patients who completed treatment submitted 79% positive urine toxicology screens over the course of the study. Patients who dropped out tended to submit fewer cocaine-positive urine screens than treatment completers. In view of suggestions that dopaminergic agents in the treatment of addictions may be enhanced when combined with serotonergic agents, a single-case study of pemoline plus fenfluramine is also reported. Except for one urine sample, all of this patient's urine screens were positive for cocaine. Although findings from these studies do not support the effectiveness of pemoline for the treatment of cocaine abuse in methadone-maintained patients, conclusions must be qualified by the lack of a control group.