title: Pharmacokinetics of ceftazidime in sheep and its penetration into tissue and peritoneal fluids.
abstract: Serum, tissue and peritoneal fluid concentrations of ceftazidime were studied in ewes after intravenous, intramuscular and subcutaneous administration at 50 mg kg-1 bodyweight. Tissue and peritoneal cages were implanted in the animals studied. After intravenous bolus administration, the mean serum concentration versus time profile was best described by a two-compartment open model. The distribution rate constant (alpha) was 3.5 +/- 1.1 h-1 and the half-life (t 1/2 alpha) 0.22 +/- 0.09 hour. The elimination rate constant (beta) was 0.43 +/- 0.04 h-1 and half-life (t 1/2 beta) 1.6 +/- 0.2 hours. The area under the curve was 275.7 +/- 84.0 micrograms.ml-1 h. The volume of distribution as steady state was 356.1 +/- 208.0 ml kg-1. The penetration ratio into tissue fluid was 62.6 +/- 15.1 per cent and into peritoneal fluid 61.1 +/- 16.5 per cent. After intramuscular injection, the elimination half-life was 1.7 +/- 0.2 hours, the area under the curve was 228.7 +/- 43.3 micrograms.ml-1 h. and the elimination rate constant was 0.42 +/- 0.05 h-1. The penetration ratio into tissue fluid was 68.5 +/- 37.3 per cent and into peritoneal fluid 73.3 +/- 34.4 per cent. After subcutaneous injection, the elimination half-life was 1.8 +/- 0.5 hours, the area under the curve was 231.8 +/- 65.6 micrograms.ml-1 h. and the elimination constant was 0.41 +/- 0.10 h-1. The penetration ratio into tissue fluid was 47.2 +/- 3.5 per cent and into peritoneal fluid 58.1 +/- 15.6 per cent.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: CIC Provincia de Buenos Aires, Cátedra de Farmacología, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina.
authors.forename: R
authors.initials: R
authors.lastname: Rule
authors.forename: M
authors.initials: M
authors.lastname: Rubio
authors.forename: M C
authors.initials: MC
authors.lastname: Perelli
mesh_terms: D000818:Animals; D001202:Ascitic Fluid / Q000378:metabolism / Q000662:veterinary*; D001682:Biological Availability; D002442:Ceftazidime / Q000008:administration & dosage / Q000493:pharmacokinetics*; D015194:Diffusion Chambers, Culture / Q000662:veterinary; D006207:Half-Life; D007273:Injections, Intramuscular / Q000662:veterinary; D007275:Injections, Intravenous / Q000662:veterinary; D007279:Injections, Subcutaneous / Q000662:veterinary; D012756:Sheep / Q000378:metabolism*; D014018:Tissue Distribution
chemical_list: D002442:Ceftazidime