Bioavailability of oral penicillins in the horse: a comparison of pivampicillin and amoxicillin

Autor: J. M. Ensink, D. J. Mevius, Arnold G. Vulto, W. R. Klein, A. Klarenbeek
Rok vydání: 1992
Předmět:
Zdroj: Journal of Veterinary Pharmacology and Therapeutics. 15:221-230
ISSN: 1365-2885
0140-7783
DOI: 10.1111/j.1365-2885.1992.tb01010.x
Popis: The pharmacokinetics of ampicillin and amoxicillin following intravenous administration at a dose rate of 15 and 10 mg/kg respectively were studied in four healthy adult horses. Pharmacokinetics of pivampicillin and amoxicillin were studied after oral administration to four healthy adult horses. Pivampicillin, a prodrug of ampicillin, was administered orally to starved and fed horses at a dose rate of 19.9 mg/kg, which is equivalent on a molecular basis to 15 mg/kg ampicillin. Amoxicillin was administered orally to starved horses only, at a dose rate of 20 mg/kg. Ampicillin and amoxicillin concentrations in plasma, synovial fluid and urine were determined. Mean biological half-life of intravenously administered ampicillin and amoxicillin was 1.72 and 1.43 h respectively, whilst the distribution volume (Vss) appeared to be 0.180 and 0.192 1/kg. Orally administered pivampicillin and amoxicillin were rapidly absorbed. A maximum concentration in plasma of 3.80 micrograms/ml was reached 2 h after administration of pivampicillin to starved horses; in fed horses a maximum concentration of 5.12 micrograms/ml was reached 1 h after administration. After oral administration of amoxicillin a maximum concentration of 2.03 micrograms/ml was reached after 1 h. The (absolute) bioavailability of pivampicillin administered orally was 30.9% in starved horses and 35.9% in fed horses. The bioavailability of amoxicillin administered orally was 5.3% in starved horses.
Databáze: OpenAIRE