Nicotinic Acid in the Prevention and Treatment of Methionine-Induced Exacerbation of Psychopathology in Schizophrenics

Abstract

In this placebo-controlled crossover study nicotinic acid, in a fixed dosage of 3000 mg. a day, produced statistically significant improvement in chronic hospitalized schizophrenic patients. We were able to reproduce the clinical observations and the results of previous workers; that is, the exacerbation of psychopathological symptoms by the combined administration of methionine and tranylcypromine. Nicotinic acid failed to prevent by prior administration or to relieve by subsequent administration, the methionine-tranylcypromine-induced exacerbation of psychopathology. This might have been due to the inadequate dosage of nicotinic acid given but the possibility of a toxic psychosis due to the metabolite, methionine sulfoximine, must be seriously considered.