Pharmacokinetic evaluation of β-lactam antibiotics

Abstract

A simple method is proposed to predict free tissue concentrations of β-lactam antibiotics from their plasma concentrations after iv bolus injection. During the elimination phase these free tissue concentrations exceed corresponding free plasma concentrations by a constant compound specific factor. This factor can be calculated from the different volumes of distribution (V_cVd_ss and V_area and the plasma protein binding. Calculation of free tissue concentrations allows more secure interpretation of pharmacokinetic data with respect to in-vitro MICs for the comparison of different antibiotics or of the same antibiotic in different patient populations.