PHARMACOKINETICS OF GENTAMICIN FOLLOWING SINGLE-DOSE PARENTERAL ADMINISTRATION TO GOATS

The disposition kinetics of parenterally administered gentamicin (5 mg kg(-1)) has been studied in Gaddi goats. The serum concentration-time profile was described by bi-exponential and monoexponential equations following intravenous (i.v.), intramuscular (i.m.) and subcutaneous ( s.c.) administration with elimination half-life values of 0.96 +/- 0.0 9, 2.37 +/- 0.47 and 3.56 +/- 0.39 h, respectively. The apparent volum e of distribution following i.v. administration (Vd(area): 0.26 +/- 0. 04 1 kg(-1)) reflected limited extracellular distribution of the drug. The bioavailability was higher following i.m. administration (96.3%) compared to s.c. (76.9%). In view of the significantly longer biologic al half-life and larger area under the curve values, the s.c. route ma y be preferred. It is concluded that a suitable and practical dosage r ecommendation for gentamicin in goats would be 3.35 mg kg(-1) body wei ght given s.c. at 12 h intervals.