Weight Changes during Clozapine Treatment

OBJECTIVE: The aim of this study was to assess the prevalence and magnitude of weight changes pre- and post-clozapine and to explore the ability of demographic and clinical factors to predict weight gain at 12 months post-clozapine. METHOD: Weight changes in a sample of 51 patients were assessed at 3 months pre-clozapine, at baseline, and at 3 and 12 months post-clozapine. In addition, demographic data and information concerning changes in appetite and activity level at 3 months was gathered and used to predict weight gain at 12 months. RESULTS: Seventy percent of patients gained an average of 7.5 kg (10.6% increase in baseline body weight) over the 12-month period. Although post-clozapine weight gain for the total group was significant at 12 months, weight gain for the female subsample (n = 16) did not reach significance at either the 3 or 12 month assessments. The only factors associated with marked weight gain (> 15% increase) at 12 months were increased food intake early in treatment and having gained weight at 3 months. CONCLUSION: Clozapine treatment was found to be associated with significant weight gain in patients prescribed clozapine, especially male patients. Considering the long-term health risks associated with excess weight gain, health professionals can play an important role in educating clients about the potential for weight gain with clozapine treatment.