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 (MTTc) are derived for intravenous drugs with linear distribution and linear or nonlinear central elimination. This R is a function of distribution clearance (CLD), dose, and area under the plasma concentration-time curve (AUC). The MTTc is a function of the central volume of distribution, CLD, dose, and AUC. The application of the proposed calculations of R and MTTc was illustrated by computer simulations.