Improving Outcomes in Psychosis Associated With Substance Use Using Aripiprazole

This project focuses on the under-researched group of individuals who develop psychotic episodes of short duration (less than four weeks) while using substances. This includes individuals diagnosed with psychotic disorder not otherwise specified (PNOS) or substance-induced psychotic disorder (SIP) AND substance abuse or dependence. Very little is known about the most appropriate maintenance/relapse prevention management of these subjects. These individuals are not diagnosed with a primary psychosis because psychotic symptoms are too short-lived or non-specific, the onset of substance use precedes the onset of psychotic symptoms and the subject has not experienced sufficient psychotic symptoms in the absence of substance use. However, previous studies have shown that they are at high risk of recurrence of psychotic symptoms. Thus, this project will assess the efficacy of the second-generation antipsychotic aripiprazole for maintenance treatment of subjects who had a recent psychotic episode of short duration associated with substance use. The investigators will compare aripiprazole and placebo for preventing the recurrence of psychotic symptoms and decreasing substance use during a 6-month maintenance phase.