Drug redistribution and mean transit time concepts for nonlinear pharmacokinetic systems

Equations for the mean number of cycles through the peripheral system ( R ) and the mean transit time through the central compartment ( MTT c ) are derived for intravenous drugs with linear distribution and linear or nonlinear central elimination. This R is a function of distribution clearance (CL D ), dose, and area under the plasma concentration–time curve (AUC). The MTT c is a function of the central volume of distribution, CL D , dose, and AUC. The application of the proposed calculations of R and MTT c was illustrated by computer simulations.