[Pharmacokinetics of synthetic sex steroids in hormonal contraceptives].

The pharmacokinetics of synthetic contraceptive steroids are dependent on several factors: e.g. body weight, ethnic factors, dosage of steroids, particle size, absorption, metabolism, elimination, affinity to proteins (SHBG, albumine), interaction etc. The dosage-dependent changes of pharmacokinetics progestagens and estrogens are presented. Besides, the principle of interactions between estrogens and progestagens and other drugs is discussed. Pharmacokinetic studies of oral contraceptive steroids should be designed according to the recommended modus of application. The analysis of the involved steroids, estrogen and progestagen, and of the combined pill should be carried out with regard to age, season and duration of application.