General treatment of linear pharmacokinetics.

A general treatment of linear pharmacokinetics that enables equations to be obtained simply for all linear compartmental models, with input in one or more compartments, is presented. Two approaches are described: one based on a full Laplace transformation and one that avoids transformation of the input functions and the use of convolution integrals. The latter approach is of particular interest when dealing with complex input functions not having a simple Laplace transform. The concept of acceptor and donor subsystems is introduced. It is demonstrated that disposition in certain models may be simplified and analyzed in terms of disposition in subsystems of simpler composition. The treatment presented is illustrated with several examples.