Tolerability and efficacy of clozapine combined with lithium in schizophrenia and schizoaffective disorder.

The safety and tolerability of clozapine combined with lithium were investigated because of potential additive risks as well as frequent usage in clinical practice. Ten hospitalized schizophrenic and 10 schizoaffective patients receiving clozapine maintenance therapy with partial therapeutic response were studied in a randomized controlled trial. CGI and PANSS outcome ratings were employed and a cognitive battery was administered at baseline and after 4 weeks of lithium and placebo administration. Barnes and UKU side effect ratings and laboratory safety data were obtained. Combined lithium-clozapine treatment was well tolerated except for reversible neurotoxic reactions in two schizophrenic patients. Safety measures showed no significant variations, even during lithium toxicity. Total WBC and absolute granulocyte counts increased with lithium and declined with placebo. Schizoaffective patients improved with lithium on CGI and PANSS total and negative symptom scales and the cognitive measures, whereas schizophrenic patients did not. Lithium added to clozapine in treatment regimens for hospitalized, treatment-resistant, schizoaffective patients appears to afford potential benefit without harmful effects; for schizophrenic patients, however, it did not afford improvement but... (PsycInfo Database Record (c) 2021 APA, all rights reserved)