title: Pharmacokinetics of levofloxacin after single intravenous and repeat oral administration to cats.
abstract: The pharmacokinetic properties of the fluoroquinolone levofloxacin, were investigated in five cats after single intravenous and repeat oral administration at a daily dose of 10 mg/kg. Levofloxacin serum concentration was analyzed by microbiological assay using Klebsiella pneumoniae ATCC 10031 as test microorganism. Serum levofloxacin disposition after intravenous and oral dosing was best fitted to a bicompartmental and a monocompartmental open models with first-order elimination, respectively. After intravenous administration, distribution was rapid (t(1/2(d)) 0.26 +/- 0.18 h) and wide as reflected by the steady-state volume of distribution of 1.75 +/- 0.42 L/kg. Drug elimination was slow with a total body clearance of 0.14 +/- 0.04 L/h.kg and a t(1/2) for this process of 9.31 +/- 1.63 h. The mean residence time was of 12.99 +/- 2.12 h. After repeat oral administration, absorption half-life was of 0.18 +/- 0.12 h and Tmax of 1.62 +/- 0.84 h. The bioavailability was high (86.27 +/- 43.73%) with a peak plasma concentration at the steady state of 4.70 +/- 0.91 microg/mL. Drug accumulation was not significant after four oral administrations. Estimated efficacy predictors for levofloxacin after either intravenous or oral administration indicate a good profile against bacteria with a MIC value below of 0.5 microg/mL. However, for microorganisms with MIC values of 1 microg/mL it would be efficacious only when administered intravenously.
authors.affiliation: Departamento de Fisiopatología y Etiopatogenia, Facultad de Ciencias Veterinarias, Universidad de Buenos Aires, Buenos Aires, Argentina. albarell@fvet.uba.ar
authors.forename: G A
authors.initials: GA
authors.lastname: Albarellos
authors.forename: L A
authors.initials: LA
authors.lastname: Ambros
authors.forename: M F
authors.initials: MF
authors.lastname: Landoni
mesh_terms: D000284:Administration, Oral; D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics* / Q000494:pharmacology; D019540:Area Under Curve; D002415:Cats / Q000378:metabolism*; D004334:Drug Administration Schedule; D005260:Female; D007275:Injections, Intravenous / Q000662:veterinary; D007711:Klebsiella pneumoniae / Q000187:drug effects; D064704:Levofloxacin; D008297:Male; D008826:Microbial Sensitivity Tests; D015242:Ofloxacin / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics* / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D064704:Levofloxacin; D015242:Ofloxacin