Objective To determine pharmacokinetic parameters for oseltamivir in all trimesters of pregnancy. Methods Thirty pregnant women, 10 per trimester, receiving oseltamivir phosphate 75 mg were recruited to study first-dose pharmacokinetics. Plasma samples were obtained at 0, 0.5, 1, 2, 4, 8, and 12 hours after the first dose. Samples were analyzed for oseltamivir and oseltamivir carboxylate levels. Using a noncompartmental model, area-under-the-curve (AUC), maximum concentration (C max ), time-to-maximum concentration (T max ), and half-life (T 1/2 ) were estimated. Results There were no significant differences in the pharmacokinetics of oseltamivir by trimester except for an increased T 1/2 in the first trimester for oseltamivir phosphate and an increased C max in the third trimester for oseltamivir carboxylate. The levels of oseltamivir carboxylate observed were within the range needed to achieve IC 50 concentrations for pandemic H1N1. Conclusion The pharmacokinetics of oseltamivir do not change significantly according to trimester of pregnancy.
【저자키워드】 oseltamivir, Influenza, Pregnancy, pahrmacokinetics,