Memantine-associated reversal of clozapine-induced weight gain.

INTRODUCTION

Weight gain is a frequently observed adverse event in the treatment with atypical antipsychotics that significantly affects the patients' physical health and treatment compliance.

METHODS

We report on a treatment-resistant schizophrenic patient who received an add-on treatment with the low-affinity NMDA antagonist memantine because of cognitive disturbances.

RESULTS

During this treatment we observed a marked decrease of clozapine-induced weight gain. The causal relationship to memantine could be demonstrated using an on-off-on design with a significant increase of weight after discontinuation and again a substantial weight loss after re-exposition with memantine. Beside weight, also negative symptoms improved.

DISCUSSION

Prospective controlled trials evaluating the safety and possible positive effects of memantine on antipsychotic induced weight gain are needed.