Clozapine plasma level monitoring for prediction of rehospitalization schizophrenic outpatients.

INTRODUCTION: The aim of this naturalistic exploratory study was to examine whether blood antipsychotic drug concentrations can predict rehospitalizations in chronically medicated patients. METHODS: The study included schizophrenic outpatients under clozapine (CLZ) maintenance treatment, supervised by therapeutic drug monitoring (TDM). Patients were observed for a period of 21 months. Their on average monthly measured plasma levels and the date of rehospitalizations were recorded. The variability of the first 3 CLZ plasma levels, measured in 3.6 months, was compared between patients with and without rehospitalization. RESULTS: 23 patients participated of which 6 patients were rehospitalized…