Abstract
Objective: People experiencing a first episode of psychosis often have co-occurring substance use, which increases risk of prolonged psychosis and impairs recovery. This article examines the prevalence of substance use in people with first-episode psychosis. Methods: The authors searched MEDLINE and other databases for articles published between 1990 and 2009 that described current or lifetime prevalence of substance use, misuse, abuse, or dependence in individuals with first-episode psychosis. Results: Forty-four unique studies provided information. More than 25% of individuals with first-episode psychosis in reviewed studies indicated current or lifetime alcohol use, lifetime alcohol abuse/dependence, current or lifetime cannabis use, or lifetime cannabis abuse or dependence. For all substances, lifetime prevalence of abuse/dependence was higher than current abuse/dependence. Conclusions: Despite variation in assessment methods, findings were generally consistent. Individuals with first-episode psychosis have lower current substance prevalence than lifetime prevalence, suggesting cessation of some substance use prior to seeking treatment for psychosis.