Salazar-Pereyra A, Rojas TIS, Ramírez-Bermúdez J, Castro-Román R, Castro-Torres NN, Jung-Cook H

Language: Spanish
References: 17
Page: 4-7
PDF size: 97.44 Kb.

ABSTRACT

The aim of this study was to determine the plasma levels of clozapine in mexican patients, and its possible relationship to dose, body weight, age, gender, smoking habits as well to establish the possible interaction with valproate and fluoxetine. Methods: steady state plasma concentrations of clozapine were evaluated in 36 patients under treatment with clozapine. Drug plasma concentrations were measured by high performance liquid chromatography with ultraviolet detection. Results: the mean plasma level of clozapine was 397 ± 260 ng/mL. Due to a considerable interindividual variation, daily doses do not correlate with levels of clozapine. No significant differences were found in plasma levels due to age and weight; however a slight trend in plasma levels due to gender and smoking habit was observed. A significant difference on plasma levels was observed between patients under monotherapy versus patients with simultaneous treatment with fluoxetine; in contrast patients under valproate treatment did not show an increase in clozapine plasma levels. The most common side effects were sialorrhea and somnolence.

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