title: Oral pharmacokinetics of acetaminophen to evaluate gastric emptying profiles of Shiba goats.
abstract: The pharmacokinetics of acetaminophen was investigated following oral dosing to Shiba goats in order to evaluate the properties of gastric emptying. Acetaminophen was intravenously and orally administered at 30 mg/kg body weight to goats using a crossover design with a 3-week washout period. The stability of acetaminophen in rumen juice was also assessed. Acetaminophen concentrations were measured by HPLC. Since acetaminophen was stable in rumen juice for 24 hr, the extremely low bioavailability (16%) was attributed to its hepatic extensive first-pass effect. The mean absorption time and absorption half-life were unexpectedly short (4.93 and 3.35 hr, respectively), indicating its marked absorption from the forestomach, which may have been due to its smaller molecular weight. Therefore, acetaminophen was considered to be unsuitable for evaluating gastric emptying in Shiba goats.
authors.affiliation: Laboratory of Veterinary Pharmacology, Department of Veterinary Medicine, Tokyo University of Agriculture and Technology, Fuchu, Tokyo 183-8509, Japan.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Elbadawy
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Sasaki
authors.forename: Yuji
authors.initials: Y
authors.lastname: Miyazaki
authors.forename: Mohamed
authors.initials: M
authors.lastname: Aboubakr
authors.forename: Waleed Fathy
authors.initials: WF
authors.lastname: Khalil
authors.forename: Minoru
authors.initials: M
authors.lastname: Shimoda
mesh_terms: D000082:Acetaminophen / Q000008:administration & dosage / Q000493:pharmacokinetics*; D000284:Administration, Oral; D000818:Animals; D019540:Area Under Curve; D001682:Biological Availability; D005746:Gastric Emptying / Q000502:physiology*; D006041:Goats / Q000502:physiology*; D006207:Half-Life; D007275:Injections, Intravenous
chemical_list: D000082:Acetaminophen