Chloramphenicol pharmacokinetics after intravenous and intramuscular administration in sheep.
The pharmacokinetics of chloramphenicol were studied after intravenous and intramuscular administration of 50 mg/kg body weight in Merino sheep. After intravenous administration, the drug was rapidly distributed extravascularly with a half-life of 10.5 +/- 8.83 min. Extensive distribution was confirmed by an apparent volume of distribution at steady state (1.5 +/- 0.43 1/kg). The elimination half-life was 3.24 +/- 0.60 h. After intramuscular injection, the absorption half-life was 44.33 +/- 19.21 min with a bioavailability of 65%. A maximum serum concentration of 15.57 +/- 3.95 micrograms/ml was determined 2 h after administration. Serum concentrations above 5 micrograms/ml were maintained for approximately 12 h with an elimination half-life of 5.75 +/- 1.25 h, longer than the half-life obtained after intravenous administration. In conclusion, the intramuscular administration of chloramphenical at a dose rate of 50 mg/kg permitted the maintenance of inhibitory concentrations of the antibiotic for the majority of Salmonella and Pasteurella isolates for at least 12 h.
Department of Pharmacology and Toxicology, Facultad de Ciencias Veterinarias, Universidad Nacional de La Plata, Buenos Aires, Argentina.
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Mestorino
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Errecalde
D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D002701:Chloramphenicol / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D005260:Female; D006207:Half-Life; D007273:Injections, Intramuscular; D007275:Injections, Intravenous; D008657:Metabolic Clearance Rate; D012756:Sheep; D014018:Tissue Distribution
D000900:Anti-Bacterial Agents; D002701:Chloramphenicol