Pharmacokinetics and metabolism of 14C-isepamicin in humans following intravenous administration.
Twelve healthy adult male volunteers received 1 g (base equivalent) of 14C-isepamicin (131 microCi) as an intravenous bolus over 5 min. The areas under the plasma concentration-time curves at infinity for isepamicin (196 micrograms*h/ml) and total radioactivity (164 micrograms*h/ml) were similar, indicating no biotransformation of isepamicin. The disappearance of isepamicin from plasma followed a triexponential decline, with half-lives of 0.17, 2.12, and 34 h for the alpha, beta, and gamma phases, respectively. However, the contribution of the gamma phase to the total area under the concentration-time curve was only 2.6%. There were no detectable metabolites in plasma and urine, confirming that isepamicin was not biotransformed. The cumulative levels of isepamicin and total radioactivity excretion in urine from 0 to 120 h were 97.3 and 92.1% of the dose, respectively, indicating that the drug was excreted mainly as unchanged isepamicin in urine.
Lin
C
C
Department of Drug Metabolism and Pharmacokinetics, Schering-Plough Research Institute, Kenilworth, New Jersey 07033, USA.
Korduba
C
C
Affrime
M
M
Radwanski
E
E
Nomeir
A
A
Batra
V
V
Cutler
D
D
Cayen
M N
MN
D000328:Adult; D000900:Anti-Bacterial Agents / Q000493:pharmacokinetics*; D002250:Carbon Radioisotopes; D005839:Gentamicins / Q000008:administration & dosage / Q000493:pharmacokinetics*; D006801:Humans; D007275:Injections, Intravenous; D008297:Male
D000900:Anti-Bacterial Agents; D002250:Carbon Radioisotopes; D005839:Gentamicins; C016927:isepamicin