title: Pharmacokinetics and milk penetration of difloxacin after intravenous, subcutaneous and intramuscular administration to lactating goats.
abstract: The single-dose disposition kinetics of difloxacin were determined in clinically normal lactating goats (n = 6) after intravenous (i.v.), subcutaneous (s.c.) and intramuscular (i.m.) administration of 5 mg/kg. Difloxacin concentrations were determined by high performance liquid chromatography with fluorescence detection. The concentration-time data were analysed by compartmental and noncompartmental kinetic methods. Steady-state volume of distribution (V(ss)) and total body clearance (Cl) of difloxacin after i.v. administration were estimated to be 1.16 +/- 0.26 L/kg and 0.32 +/- 0.05 L/h x kg respectively. Following s.c. and i.m. administration difloxacin achieved maximum plasma concentrations of 1.33 +/- 0.25 and 1.97 +/- 0.40 mg/L at 3.37 +/- 0.36 and 1.79 +/- 1.14 h respectively. The absolute bioavailabilities after s.c. and i.m. routes were 90.16 +/- 11.99% and 106.79 +/- 13.95% respectively. Difloxacin penetration from the blood into the milk was extensive and rapid, and the drug was detected for 36 h after i.v. and s.c. dosing, and for 72 h after i.m. administration.
authors.affiliation: Department of Pharmacology, Faculty of Veterinary Medicine, University of Murcia, Campus de Espinardo, Murcia, Spain. pmarin@um.es
authors.forename: P
authors.initials: P
authors.lastname: Marín
authors.forename: E
authors.initials: E
authors.lastname: Escudero
authors.forename: E
authors.initials: E
authors.lastname: Fernández-Varón
authors.forename: C M
authors.initials: CM
authors.lastname: Cárceles
mesh_terms: D000818:Animals; D000890:Anti-Infective Agents / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D019540:Area Under Curve; D002939:Ciprofloxacin / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000097:blood / Q000493:pharmacokinetics; D018592:Cross-Over Studies; D005260:Female; D024841:Fluoroquinolones / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D006041:Goats / Q000378:metabolism*; D007273:Injections, Intramuscular / Q000662:veterinary; D007275:Injections, Intravenous / Q000662:veterinary; D007279:Injections, Subcutaneous / Q000662:veterinary; D007774:Lactation; D008892:Milk / Q000378:metabolism*
chemical_list: D000890:Anti-Infective Agents; D024841:Fluoroquinolones; D002939:Ciprofloxacin; C047225:difloxacin