Pharmacokinetics of ceftiofur sodium and ceftiofur crystalline free acid in neonatal foals

• Published in: Journal of veterinary pharmacology and therapeutics Vol. 34; no. 4; pp. 403 - 409
• Main Authors: HALL, T.L, TELL, L.A, WETZLICH, S.E, McCORMICK, J.D, FOWLER, L.W, PUSTERLA, N
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.08.2011
• Subjects: adverse effects; Animals; Anti-Bacterial Agents - administration & dosage; Anti-Bacterial Agents - blood; Anti-Bacterial Agents - pharmacokinetics; body weight; ceftiofur; Cephalosporins - administration & dosage; Cephalosporins - blood; Cephalosporins - pharmacokinetics; Chromatography, High Pressure Liquid - veterinary; Female; foals; half life; high performance liquid chromatography; Horses - metabolism; Injections, Intravenous - veterinary; Injections, Subcutaneous - veterinary; intravenous injection; Male; metabolites; microorganisms; pathogens; pharmacokinetics; subcutaneous injection
• ISSN: 0140-7783; 1365-2885
• DOI: 10.1111/j.1365-2885.2010.01252.x

Hall, T. L., Tell, L. A., Wetzlich, S. E., McCormick, J. D., Fowler, L. W., Pusterla, N. Pharmacokinetics of ceftiofur sodium and ceftiofur crystalline free acid in neonatal foals. J. vet. Pharmacol. Therap.34, 403-409. Ceftiofur, a third generation cephalosporin, demonstrates in vitro efficacy against microorganisms isolated from septicemic neonatal foals. This pharmacokinetic study evaluated the intravenous and subcutaneous administration of ceftiofur sodium (5 mg/kg body weight; n = 6 per group) and subcutaneous administration of ceftiofur crystalline free acid (6.6 mg/kg body weight; n = 6) in healthy foals. Plasma ceftiofur- and desfuroylceftiofur-related metabolite concentrations were measured using high performance liquid chromatography following drug administration. Mean (±SD) noncompartmental pharmacokinetic parameters for i.v. and s.c. ceftiofur sodium were: AUC₀→∝ (86.4 ± 8.5 and 91 ± 22 h·μg/mL for i.v. and s.c., respectively), terminal elimination half-life (5.82 ± 1.00 and 5.55 ± 0.81 h for i.v. and s.c., respectively), Cmax₍obs₎ (13 ± 1.9 μg/mL s.c.), Tmax₍obs₎ (0.75 ± 0.4 h for s.c.). Mean (± SD) noncompartmental pharmacokinetic parameters for s.c. ceftiofur crystalline free acid were: AUC₀→∝ (139.53 ± 22.63 h·μg/mL), terminal elimination half-life (39.7 ± 14.7), Cmax₍obs₎ (2.52 ± 0.35 μg/mL) and tmax₍obs₎ (11.33 ± 1.63 h). No adverse effects attributed to drug administration were observed in any foal. Ceftiofur- and desfuroylceftiofur-related metabolites reached sufficient plasma concentrations to effectively treat common bacterial pathogens isolated from septicemic foals.