title: Disposition and oral bioavailability of amoxicillin and clavulanic acid in pigs.
abstract: The pharmacokinetic properties of amoxicillin and clavulanic acid were studied in healthy, fasted pigs after single intravenous (i.v.) and oral (p.o.) dosage of 20 mg/kg of amoxicillin and 5 mg/kg of clavulanic acid. The plasma concentrations of the drugs were determined by validated high-performance liquid chromatographic methods and the pharmacokinetic parameters were calculated by compartmental and noncompartmental analyses. After i.v. administration of the two drugs, plasma concentration-time curves were best described by a three-compartmental open model for amoxicillin and a two-compartmental open model for clavulanic acid. Amoxicillin (with a t(1/2 gamma) = 1.03 h and a clearance of 0.58 L/h.kg) and clavulanic acid (with a t(1/2 beta) of 0.74 h and a clearance of 0.41 L/h.kg) were both rapidly eliminated from plasma. Both drugs had apparently the same volume of distribution of 0.34 L/kg. After p.o. administration of the two drugs, a noncompartmental model was used. Elimination half-lives of amoxicillin and clavulanic acid were not significantly different, i.e. 0.73 and 0.67 h respectively. The mean maximal plasma concentrations of amoxicillin and clavulanic acid were 3.14 and 2.42 mg/L, and these were reached after 1.19 and 0.88 h respectively. The mean p.o. bioavailability was found to be 22.8% for amoxicillin and 44.7% for clavulanic acid.
authors.affiliation: Department of Pharmacology, Toxicology, Biochemistry and Organ Physiology, Ghent University, Merelbeke, Belgium. tim.reyns@ugent.be
authors.forename: T
authors.initials: T
authors.lastname: Reyns
authors.forename: S
authors.initials: S
authors.lastname: De Boever
authors.forename: K
authors.initials: K
authors.lastname: Baert
authors.forename: S
authors.initials: S
authors.lastname: Croubels
authors.forename: S
authors.initials: S
authors.lastname: Schauvliege
authors.forename: F
authors.initials: F
authors.lastname: Gasthuys
authors.forename: P
authors.initials: P
authors.lastname: De Backer
mesh_terms: D000284:Administration, Oral; D000658:Amoxicillin / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D019540:Area Under Curve; D001682:Biological Availability; D019818:Clavulanic Acid / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D018592:Cross-Over Studies; D005260:Female; D013552:Swine / Q000378:metabolism*
chemical_list: D000900:Anti-Bacterial Agents; D019818:Clavulanic Acid; D000658:Amoxicillin