Amikacin Serum Concentrations: Prediction of Levels and Dosage Guidelines

Abstract

Amikacin is a new aminoglycoside antibiotic that behaves pharmacokinetically similar to kanamycin, gentamicin, and tobramycin. Our study was designed to test whether a digital computer program could correctly predict amikacin serum concentrations in the clinical setting. A significant relation (P < 0.0001) was found between 153 measured (bioassayed) and computer-predicted levels from 26 patients. The computer program reliably estimated amikacin serum levels after either intravenous or intramuscular doses. Prediction accuracy was not significantly affected by patient sex, hematocrit, or periods of unstable renal function. Predicted levels were most accurate when based on creatinine clearance corrected to 70 kg body weight or corrected to body surface area. The pharmacokinetic parameters in the computer program were used to generate a new aminoglycoside dosing chart. Ten patients were given amikacin according to this guideline, and the mean peak serum level for the group was 25.6 μg/ml.