Metformin for obesity and glucose dysregulation in patients with schizophrenia receiving antipsychotic drugs.

Antipsychotic drug-induced weight gain and glucose dysregulation add to the cardiovascular risk of patients with schizophrenia and contribute to their early mortality. The currently recommended interventions to address the metabolic complications of antipsychotic drug treatment are to switch the patient from an antipsychotic drug with high metabolic liability to one with a lower liability and to implement lifestyle changes. These interventions can be quite challenging to carry out. So far the progress in improving the metabolic and cardiovascular outcome of patients with major mental illness has been disappointing. We offer an overview of the literature on metformin for antipsychotic drug-induced weight gain and glucose dysregulation and pertinent literature from the Diabetes Prevention Program. We conclude that young adults with schizophrenia newly exposed to antipsychotic drugs, who show a pattern of rapid weight gain and/or glucose dysregulation, are prime candidates for metformin if switching the antipsychotic medication to one with a lower metabolic burden is not an option or does not curtail the weight gain and/or adverse metabolic effects. Metformin therapy should not preclude healthy lifestyle interventions.