Kinetics of kavain and its metabolites after oral application.
Kavain metabolism in humans was the target of this current investigation. In the present study a high-performance liquid chromatographic (HPLC-DAD) assay method for the simultaneous determination of kavain and its main metabolites (p-hydroxykavain, p-hydroxy-5,6-dehydrokavain and p-hydroxy-7,8-dihydrokavain) in serum and urine was developed and validated. The metabolites were mainly excreted in the form of their conjugates. All kavain metabolites were detectable in serum and urine, except for p-hydroxy-7,8-dihydrokavain, which was found in urine only. Confirmation of the results and identification of the metabolites were performed by LC-MS or LC-MS-MS. Kinetics of kavain and its metabolites in serum were investigated after administration of a single oral dose (800 mg kavain). Within 1 and 4 h after uptake, the serum concentrations ranged between 40 and 10 ng/ml for kavain, 300 and 125 ng/ml for p-hydroxykavain, 90 and 40 ng/ml for o-desmethyl-hydroxy-5,6-dehydrokavain, and 50 and 30 ng/ml for 5,6-dehydrokavain.
Tarbah
F
F
Institute of Legal Medicine, Heinrich-Heine University, PO Box 10 10 07, D-40001, Duesseldorf, Germany. fortoxi@uni-duesseldorf.de
Mahler
H
H
Kardel
B
B
Weinmann
W
W
Hafner
D
D
Daldrup
Th
T
D000284:Administration, Oral; D001711:Biotransformation; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D006801:Humans; D011753:Pyrones / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics* / Q000652:urine; D012015:Reference Standards; D015203:Reproducibility of Results
D011753:Pyrones; C011889:kavain