Pharmacokinetics of intramuscularly administered isepamicin in man

The pharmacokinetics of isepamicin, a broad-spectrum aminoglycoside antibiotic, was studied in man after intramuscular administration. Two groups each of 6 volunteers received isepamicin for 10 consecutive days by intramuscular injection at respective doses of 7.5 mg/kg once daily or 7.5 mg/kg twice daily. Plasma and urinary concentrations of isepamicin were determined using a specific HPLC method. In both groups, there was no drug accumulation following multiple administration. The t(1/2), which ranged from 2.4 to 2.7 h, was independent of the dosage regimen. Isepamicin excreted into (0-24 h) urine accounted for virtually 100% of the dose. The results show that the pharmacokinetics of isepamicin are similar with these dosage regimens. The drug undergoes no detectable biotransformation, does not accumulate upon multiple dosing, and is cleared solely by urinary excretion.