Minimizing weight gain for patients taking antipsychotic medications: The potential role for early use of metformin.

Background: Patients taking antipsychotic medications are at high risk for weight gain, which in turn leads to poor health outcomes, nonadherence with treatment, and low self-esteem.

Methods: We reviewed published studies of pharmacologic interventions aimed at minimizing antipsychotic-induced weight gain. Treatments initiated prior to onset of weight gain were compared with those that started once weight gain already had occurred.

Results: Although data are limited, adjunctive medications for weight management appear to be more effective when initiated at or near the time when patients are first exposed to antipsychotic medications. Interventions initiated later in the course of treatment-typically after weight gain already has occurred-rarely help patients return to their pretreatment weight. The most commonly used adjunctive intervention has been metformin.

Conclusions: Certain patients benefit from initiating metformin early in their exposure to second-generation antipsychotic agents. In particular, young, healthy patients beginning olanzapine or clozapine probably will experience less weight gain if they concomitantly initiate metformin.