Pharmacokinetics and dosage regimen of ceftriaxone following its single intramuscular administration in kagani breed of goats (Capra Hircus)

The pharmacokinetic and dosage regimen of ceftriaxone sodium were computed in Kagani breed of goats (n=5) by Microbiological assay method after a single intramuscular administration @ 10mg/kg. The blood plasma antibiotic levels were determined by using Escherichia coli ATCC 25922 as a test microorganism. The limit of quantification was 0.2 ì g.ml⁻¹. Plasma ceftriaxone pharmacokinetics was analysed by one compartment open model using least square regression method. Appreciable concentration (12.19 ± 2.27 μg.ml⁻¹) was measured at 2.5 min. and peak plasma level (26.40 ± 3.33 μg.ml⁻¹) was achieved at 20 min. The value of absorption half life (t_½Ka), elimination half life (t_½â) 0.20 ± 0.05 h and 0.98 ± 0.08 h, respectively. The apparent volume of distribution (Vd_area) and total body clearance (Cl_B) were 0.48 ± 0.10 L. Kg⁻¹ and 0.34 ± 0.06 L. Kg⁻¹.h⁻¹, respectively. To maintain a minimum therapeutic concentration of 1.0 μg.ml⁻¹, a satisfactory intramuscular dosage regimen of ceftriaxone is 3.56 mg.kg⁻¹ and 15.50 mg.kg⁻¹, repeated at 6 and 8 hourly, respectively.