Notes that research investigating the comorbidity between eating disorders and substance-use disorders have reported positive but contrasting results. The aim of this study was to further explore this association by studying patterns of consumption of the entire range of psychoactive substances (alcohol, specific drugs, prescribed psychotropics) in a large sample (271 female Ss; aged 15-40 yrs) of eating-disorder Diagnostic and Statistical Manual of Mental Disorders-IV (DSM-IV) subtypes. Results show that Ss suffering from anorexia of the restrictive type show significantly less drug-consumption behaviors and alcohol abuse and/or dependence disorders than purging anorexic and bulimic Ss. No difference was found in the total consumption of psychotropics among the 4 groups of eating disorders. However, more than half of eating disorder Ss are regular consumers of psychotropics. Among these regular consumers, bulimics self-prescribe and increase their doses of psychotropics significantly more than anorexics. Features of impulsivity that are associated with purging and bulimic behaviors could play a specific role in these patterns of comorbidity and account for such differences. (PsycINFO Database Record (c) 2004 APA, all rights reserved)