This study represents a randomized, double blind placebo-controlled trial. Thirty cocaine dependant patients will be included in this study during their hospitalization for withdrawal. After the inclusion visit, they will be randomized to receive disulfiram 250 mg/day or placebo over the 15 days of their hospitalization. Main outcome criteria will be evaluated during two TEP imaging sessions with 11Craclopride, before and after stimulation by methylphenidate, 8 to 15 days after randomization.