Pharmacokinetics and Dosage Regimen of Cefpirome in Febrile Cross-Bred Calves

The pharmacokinetics of cefpirome after a single intravenous injection of 10 mg.kg-1 was studied in febrile cross-bred calves. E. coli endotoxin was administered intravenously to induce fever in calves. Blood samples were collected at different time intervals and cefpirome levels were estimated by using microbiological assay technique. Based on the plasma drug levels, the pharmacokinetic parameters were determined. Maximum concentration of cefpirome was attained at 1 min and the drug was detected above MIC in plasma up to 12 h after its administration. The values of t1/2α, Vdarea and AUC were 0.06 ± 0.003 h, 0.75 ± 0.02 L.kg-1 and 36.6 ± 0.82 μg.ml-1.h. The high values of t1/2β (1.90 ± 0.03 h) and ClB (0.27 ± 0.006 L.kg-1.h-1) reflected rapid elimination and body clearance of the drug in febrile calves. The study suggested that cefpirome was rapidly distributed and rapidly eliminated in febrile crossbred calves.