한국인에서의 경구용 클로나제팜의 약물동력학적 특성

Pharmacokinetic Characteristics of Oral Clonazepam in Korean

In order to determine the bioavailability of clonazepam, an anxiolytic drug, a simple, rapid and sensitive HPLC analysis was developed in healthy Korean volunteers. The analysis system was validated in specificity accuracy, precision and linearity. The analysis condition we established was 2.58 min and 5 ng/ml in retention time and limit of quantitation of clonazepam, respectively, using reverse-phase Cl8 column connected to UV detector. Quantitation was performed at 235 nm wave length with p- hydroxybengoic acid ethyl ester as internal standard. The method involved a simple extraction. In order to study blood level profiles as a function of time, eight volunteers were enrolled and orally took 6 mg clonazepam once. The blood samples were collected from 0 to 120 h after the drug administration. Mean AUC and Cmax value were 1028.17±568.165 (ng/ml.hr) and 41.25±10.82 (ng/ml,respectively. And mean Tmax and T1/2 value were 1.08±0.42 (hr) and 30.78±3.26(hr). From the results we determine the pharmacokinetic characteristics of clonazepam in Korean people using a newly developed and useful HPLC method.