Premium
Single and multiple‐dose pharmacokinetics of tepoxalin and its active metabolite after oral administration to rabbits ( Oryctolagus cuniculus )
Author(s) -
POLLOCK C. G.,
CARPENTER J. W.,
KOCH D. E.,
HUNTER R. P.
Publication year - 2008
Publication title -
journal of veterinary pharmacology and therapeutics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.527
H-Index - 60
eISSN - 1365-2885
pISSN - 0140-7783
DOI - 10.1111/j.1365-2885.2007.00937.x
Subject(s) - metabolite , pharmacokinetics , active metabolite , oral administration , plasma concentration , pharmacology , drug administration , chemistry , medicine , chromatography
The anti‐inflammatory agent, tepoxalin, was administered to eight healthy 6‐month‐old female New Zealand white rabbits once daily at an oral dose of 10 mg/kg. Blood samples were obtained immediately before and at 0.25, 0.5, 1, 2, 3, 4, 6, 8, 12, and 24 h postadministration on days 1 and 10. Tepoxalin and its active metabolite, RWJ 20142, concentrations were determined in plasma by use of high‐performance liquid chromatography with mass spectrometry. C max of the parent compound was reached between 3 and 8 h of drug administration, with a harmonic mean t 1/2 of 3.6 h. Peak tepoxalin plasma concentrations were 207 ± 49 ng/mL. After oral administration, the metabolite RWJ 20142 achieved C max in plasma 2–8 h after administration, with a t 1/2 of 1.9–4.8 h (harmonic mean 2.8 h). Peak plasma concentrations of RWJ 20142 on day 1 were 2551 ± 1034 ng/mL.