Relationship between clinical efficacy and clozapine concentrations in plasma in schizophrenia: effect of smoking

摘要: Concentrations in plasma of clozapine and norclozapine, the major metabolite clozapine, were measured 59 treatment-resistant schizophrenic patients at a random time period during course treatment. A lower sum concentrations norclozapine or either alone predicted less improvement Brief Psychiatric Rating Scale (BPRS) Total Positive symptoms multivariate analysis that controlled for baseline BPRS rating dose. The mean doses after 6 months treatment blood sampling not significantly different 30 responders 29 nonresponders to on basis decrease scores, whereas their higher responders. Clozapine correlated both with dose months. concentration 370 ng/ml was optimal cutoff distinguishing from nonresponders. did differ male smokers nonsmokers.