Therapeutic drug monitoring of clozapine and relapse a retrospective study of routine clinical data

Abstract

It is tentatively concluded that serum levels of clozapine < 50 ng/ml are related to relapse irrespective of concurrent psychotropic drugs. In cases where there are no concurrent psychotropic drugs, serum levels of clozapine < 250 ng/ml are associated with relapse. The risk of relapse is low for serum levels of clozapine > 250 ng/ml irrespective of concurrent psychotropic drugs. The risk of intoxication is increased with serum levels > 750 ng/ml. The TDM of clozapine is recommended during maintenance treatment.