Optimal Sampling Times of Once Daily Gentamicin in Korean Patients with Urinary Tract Infections

Abstract

The clinical use of once daily aminoglycoside (ODA) dosing has been increased because of the poten-tial therapeutic advantages of this dosing regimen. To evaluate the optimal sampling times of ODA dosing methodin a clinical setting, the study was prospectively conducted in a total of 28 patients with UTI. All of the patientswere intravenously administered gentamicin at a dose of 7 mg/kg over 60 minutes and randomly divided into twogroups. Blood was collected at 0, 2, and 6 hours in Group A and at 1, 2, and 6 hours in Group B after the end of 1-hour infusion. The pharmacokinetic parameters (Ke, Vd and Cmax) obtained using the 0, 6 hour levels and 2, 6hour levels in Group A were statistically different while those of 1, 6 hour levels and 2, 6 hour levels in Group Bwere similar. This finding indicated that the distributional phase of ODA is completed within 1 hour following theend of the 1-hour infusion. If we are allowed to collect only two blood samples in ODA considering patients com-fort and the analytical cost of drug, the first one should be drawn after 1 hour following the end of infusion toobtain adequate pharmacokinetic information.Keywords□ once daily gentamicin, optimal sampling times, pharmacokinetic parameter