Pharmacokinetics and Dosage Regimen of Ceftriaxone in Buffalo Calves

The pharmacokinetics and dosage regimen of ceftriaxone were investigated in buffalo calves (n = 6) following a single intravenous administration of ceftriaxone (10 mg/kg). The elimination rate constant was 0.18±0.01 h–1 and the elimination half-life was 3.79±0.09 h. The apparent volume of distribution (Vd(area)) was 1.40±0.01 L/kg and the total plasma clearance was 0.26±0.01 L/(kg h). Approximately 43% of total administered dose of ceftriaxone was excreted in urine within 8 h. To maintain a minimum therapeutic concentration of 1 μg/ml, a satisfactory intravenous dosage regimen of ceftriaxone in buffalo calves is 13 mg/kg repeated at 12 h intervals.