Metformin for the prevention of clozapine-induced weight gain

Acta Psychiatrica ScandinavicaScott Cunningham MD PhD, et al. | June 27, 2022



Premature mortality in schizophrenics has been attributed, in part, to the antipsychotic medication (most notably, clozapine)-associated weight gain, dyslipidemia, insulin resistance, and diabetes, all of which increase the risk for cardiovascular disease. This study clearly showed the metabolic benefits of metformin add-on to patients prescribed clozapine.

The medical charts of clozapine new starts (n=396) on clozapine alone (n=329) or clozapine with metformin (n=69) were reviewed. The primary and secondary outcomes were weight gain and metabolic changes 6 and 12 months after starting clozapine, respectively.

The clozapine + metformin group had less weight gain than the clozapine only group 6 months (-0.15 kg vs. +2.99 kg) and 12 months after starting clozapine (-0.67 kg vs. +4.72 kg). The clozapine + metformin group had a favorable effect on glucose and triglyceride levels.