PHARMACOKINETICS OF GENTAMICIN FOLLOWING SINGLE-DOSE INTRAVENOUS ADMINISTRATION IN NORMAL AND FEBRILE GOATS

A pharmacokinetic study of gentamicin (5 mg/kg intravenous (i.v.)) was conducted first in clinically healthy female goats and then in the same goats after induction of fever by Escherichia coli endotoxin (0.2 mug/kg i.v.). Rectal temperature increased 1-degrees to 1.5-degrees-C in febrile goats. Differences in the blood serum concentrations of gentamicin were not observed at any time between febrile and normal goats. The disposition kinetics of gentamicin were described by a biexponential expression C(P) = Ae(-alphat) + Be(-betat). Median values for the half-lives of gentamicin were 103.6 min in normal and 136.0 min in febrile goats. The apparent volume of distribution (V(d)) was 263.3 ml/kg in the febrile goats which was not different from that in the normal goats (240.6 ml/kg). The volume of the central compartment (V(c)) was almost identifical in normal and febrile goats. The body clearance (Cl(beta)) was observed to be 1.7 and 1.6 ml/min.kg in normal and febrile goats, respectively. Dosage regimes for gentamicin were calculated on the basis of median kinetic data.