Background. Though methadone effectively treats opioid dependence in polydrug users, some abstinent patients relapse to maladaptive use of cocaine during treatment. Relapse may be triggered by cocaine-associated cues. Work in a rodent relapse model has demonstrated that the atypical neuroleptic drug aripiprazole (Abilify), a partial agonist at dopamine D2 receptors, can block relapse to cocaine use induced by cocaine-associated environmental stimuli or by priming doses of cocaine.