title: Pharmacokinetic behaviour of enrofloxacin and its metabolite ciprofloxacin after subcutaneous administration in cattle.
abstract: This study compared pharmacokinetic profiles in cattle dosed subcutaneously with two different formulations of enrofloxacin (5% and 10%) at a dose of 5 mg/kg. Plasma concentrations of enrofloxacin and its active metabolite, ciprofloxacin, were determined by a HPLC/u.v. method. The pharmacokinetic parameters of enrofloxacin and its metabolite were similar in both injectable formulations. Enrofloxacin peak plasma concentration (5%: 0.73 +/- 0.32; 10%: 0.60 +/- 0.14 microg/mL) was reached at 1.21 +/- 0.52 and 1.38 +/- 0.52 h to 5 and 10%, respectively. The terminal half-live and area under curve were 2.34 +/- 0.46 and 2.59 +/- 0.46 h, and 3.09 +/- 0.81 and 2.93 +/- 0.58 microg x h/mL, to 5 and 10%, respectively. The AUC/MIC(90) and Cmax/MIC(90) ratios for both formulations exceed the proposed threshold values for optimized efficacy and minimized resistance development whilst treating infections or septicaemia caused by P. multocida and E. coli.
authors.affiliation: Cátedra de Farmacología, Dpto. Farmacología y Toxicología, Facultad de Veterinaria, Universidad Complutense de Madrid, Ciudad Universitaria, 28040 Madrid, Spain.
authors.forename: J J
authors.initials: JJ
authors.lastname: de Lucas
authors.forename: M I
authors.initials: MI
authors.lastname: San Andrés
authors.forename: F
authors.initials: F
authors.lastname: González
authors.forename: R
authors.initials: R
authors.lastname: Froyman
authors.forename: C
authors.initials: C
authors.lastname: Rodríguez
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000097:blood / Q000493:pharmacokinetics* / Q000633:toxicity; D002417:Cattle / Q000097:blood / Q000378:metabolism*; D002939:Ciprofloxacin / Q000097:blood / Q000493:pharmacokinetics*; D000077422:Enrofloxacin; D024841:Fluoroquinolones / Q000097:blood / Q000493:pharmacokinetics* / Q000627:therapeutic use; D008297:Male
chemical_list: D000900:Anti-Bacterial Agents; D024841:Fluoroquinolones; D000077422:Enrofloxacin; D002939:Ciprofloxacin