1. Enrofloxacin and marbofloxacin in horses: comparison of pharmacokinetic parameters, use of urinary and metabolite data to estimate first-pass effect and absorbed fraction
- Author
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Alain Bousquet-Mélou, Valérie Laroute, Mathieu Peyrou, André Vrins, Michèle Doucet, Physiologie et Toxicologie Expérimentales, Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Vétérinaire de Toulouse (ENVT), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, Ecole Nationale Vétérinaire de Toulouse (ENVT), and Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National de la Recherche Agronomique (INRA)
- Subjects
animal diseases ,Metabolite ,Administration, Oral ,Urine ,Quinolones ,Pharmacology ,030226 pharmacology & pharmacy ,0403 veterinary science ,chemistry.chemical_compound ,0302 clinical medicine ,Anti-Infective Agents ,Ciprofloxacin ,Oral administration ,MESH: Animals ,Enzyme Inhibitors ,MESH: Biological Availability ,Enrofloxacin ,04 agricultural and veterinary sciences ,3. Good health ,MESH: Enzyme Inhibitors ,Area Under Curve ,Injections, Intravenous ,Administration ,MESH: Administration, Oral ,Female ,Intravenous ,Half-Life ,Fluoroquinolones ,MESH: Half-Life ,medicine.drug ,Oral ,040301 veterinary sciences ,MESH: Anti-Infective Agents ,Biological Availability ,Injections ,03 medical and health sciences ,First pass effect ,Animal science ,Marbofloxacin ,Pharmacokinetics ,medicine ,Animals ,Horses ,MESH: Ciprofloxacin ,MESH: Horses ,MESH: Quinolones ,General Veterinary ,MESH: Fluoroquinolones ,MESH: Injections, Intravenous ,Bioavailability ,chemistry ,[SDV.SP.PHARMA]Life Sciences [q-bio]/Pharmaceutical sciences/Pharmacology ,MESH: Area Under Curve ,MESH: Female - Abstract
International audience; Enrofloxacin and marbofloxacin are two veterinary fluoroquinolones used to treat severe bacterial infections in horses. A repeated measures study has been designed to compare their pharmacokinetic parameters, to investigate their bioavailability and to estimate their absorbed fraction and first-pass effect by using plasma, urinary and metabolite data collected from five healthy mares. Clearance and V(d(ss)) were greater for enrofloxacin (mean +/- SD = 6.34 +/- 1.5 mL/min/kg and 2.32 +/- 0.32 L/kg, respectively) than for marbofloxacin (4.62 +/- 0.67 mL/min/kg and 1.6 +/- 0.25 L/kg, respectively). Variance of the AUC(0-inf) of marbofloxacin was lower than that for enrofloxacin, with, respectively, a CV = 15% and 26% intravenously and a CV = 31% and 55% after oral administration. Mean oral bioavailability was not significantly different between marbofloxacin (59%) and enrofloxacin (55%). The mean percentage of the dose eliminated unchanged in urine was significantly higher for marbofloxacin (39.7%) than that for enrofloxacin (3.4%). Absorbed fraction and first-pass effect were only determinable for enrofloxacin, whereas the percentage of the dose absorbed in the portal circulation was estimated to be 78% and the fraction not extracted during the first pass through the liver was 65%. Consequently, the moderate observed bioavailability of enrofloxacin appears to be mainly caused by hepatic first-pass effect.
- Published
- 2006