Weight gain in schizophrenic patients during chemotherapy was first reported with chlorpromazine. Since then other antipsychotic drugs have exhibited this effect, while some have reduced weight. A retrospective review of 78 schizophrenic patients revealed that thiothixene, fluphenazine, haloperidol, and thioridazine produced a mean weight gain and loxapine a mean weight loss after 12 and 36 weeks of treatment. The ability of an effective antipsychotic drug, such as loxapine, to prevent weight gain or to produce weight loss offers a clinical advantage in the treatment of those schizophrenic patients where weight gain should be a problem.