The non-linear pharmacokinetics of prednisone and prednisolone. I. Theoretical.

Three simple linear and three simple non-linear pharmacokinetic models are presented which incorporate the reversible metabolism that occurs between prednisone and prednisolone. Under steady-state conditions it is possible to not only distinguish between the linear and non-linear models but also to determine which particular model of each group applies to a given set of data. While the non-linear conversion of prednisolone to prednisone is important in explaining the pharmacokinetics of prednisone in all three non-linear models, the same is not true for prednisolone.