Analytical study of three-compartment pharmacokinetic models: concentration, area under curves, mean residence time.

The analytical expression for the drug concentration in each of the three compartments of a pharmacokinetic model, following any type of administration, is obtained from the transfer or elimination coefficients alone, without numerical approximation. Important applications of this result are the fitting of experimental data and the calculation of the areas under concentration curves or of the mean residence time of the drug in a given compartment or in the system as a whole.