The effects of clozapine on alcohol and drug use disorders among patients with schizophrenia

Several case studies indicate that clozapine use is associated with reducti ons in the use of nicotine, alcohol, or illicit drugs. Although not designe d to assess clozapine, this study explored a posteriori the effects of cloz apine on alcohol and drug use disorders among schizophrenia patients. Among 151 patients with schizophrenia or schizoaffective disorder and co-occurri ng substance use disorder who mere studied in a dual-disorder treatment pro gram, 36 received clozapine during the study for standard clinical indicati ons. All participants were assessed prospectively at baseline and every 6 m onths over 3 years for psychiatric symptoms and substance use, Alcohol-abus ing patients taking clozapine experienced significant reductions in severit y of alcohol abuse and days of alcohol use while on clozapine, For example, they averaged 54.1 drinking days during 6-month intervals while off clozap ine and 12.5 drinking days while on clozapine, They also improved more than patients who did not receive clozapine, At the end of the study, 79.0 perc ent of the patients on clozapine mere in remission from alcohol use disorde r for 6 months or longer, while only 33.7 percent of those not taking cloza pine mere remitted. Findings related to other drugs in relation to clozapin e were also positive but less clear because of the small number of patients with drug use disorders. This study was limited by the naturalistic design and the lack of prospective, standardized measures of clozapine use. The u se of clozapine by patients with co-occurring substance disorders deserves further study in randomized clinical trials.