Modelling of the passage of drugs into milk.

Pharmacokinetic modelling of plasma to milk transfer of drugs has assisted our understanding of the milk to plasma ratio (M/P) and pitfalls associated with it. The most useful way of measuring M/P ratios is, however, by model independent analysis. Physiological models have been proposed to enable the prediction of M/P ratios. The most accurate in prospective performance is the log-transformed phase distribution model. This model, developed by stepwise multiple linear regression analysis, also assists in the understanding of the relative contribution of the various physiological factors involved in the distribution of drugs into milk.