OBJECTIVE: The purpose of this study was to determine if plasma clozapine levels were associated with treatment response. METHOD: To examine this question, neuroleptic nonresponsive patients with schizophrenia or schizoaffective disorder were given clozapine, which was titrated to 500 mg/day by day 14 of treatment, and the dose was held fixed at least through day 21. Subsequently, clozapine doses were adjusted as clinically indicated, up to a maximum of 900 mg/day. Plasma clozapine levels were obtained at weeks 3 and 6, and standard clinical ratings (Brief Psychiatric Rating Scale [BPRS] and Clinical Global Impression) were done at baseline and at weeks 3 and 6. RESULTS: Data from 45 subjects were analyzed. There were no correlations between plasma clozapine levels and change in BPRS scores at treatment weeks 3 and 6. However, when the subjects were classified as responders or nonresponders, therapeutic response was associated with clozapine blood levels above 350 ng/ml. CONCLUSIONS: This study suggest that clozapine blood levels are correlated with clinical response.
OBJECTIVE: The purpose of this study was to determine if plasma clozapine levels were associated with treatment response. METHOD: To examine this question, neuroleptic nonresponsive patients with schizophrenia or schizoaffective disorder were given clozapine, which was titrated to 500 mg/day by day 14 of treatment, and the dose was held fixed at least through day 21. Subsequently, clozapine doses were adjusted as clinically indicated, up to a maximum of 900 mg/day. Plasma clozapine levels were obtained at weeks 3 and 6, and standard clinical ratings (Brief Psychiatric Rating Scale [BPRS] and Clinical Global Impression) were done at baseline and at weeks 3 and 6. RESULTS: Data from 45 subjects were analyzed. There were no correlations between plasma clozapine levels and change in BPRS scores at treatment weeks 3 and 6. However, when the subjects were classified as responders or nonresponders, therapeutic response was associated with clozapine blood levels above 350 ng/ml. CONCLUSIONS: This study suggest that clozapine blood levels are correlated with clinical response.
Authors: K H Kho; B A Blansjaar; S de Vries; D Babuskova; A H Zwinderman; D H Linszen Journal: Eur Arch Psychiatry Clin Neurosci Date: 2004-11-12 Impact factor: 5.270
Authors: Robert W Buchanan; Julie Kreyenbuhl; Deanna L Kelly; Jason M Noel; Douglas L Boggs; Bernard A Fischer; Seth Himelhoch; Beverly Fang; Eunice Peterson; Patrick R Aquino; William Keller Journal: Schizophr Bull Date: 2009-12-02 Impact factor: 9.306