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 microgram/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 CP = Ae-alpha t + Be-beta t. 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 (Vd) 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 (Vc) was almost identical 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 regimens for gentamicin were calculated on the basis of median kinetic data.