口服甾体避孕药是近代普遍使用的药物之一。服用对象多数是健康妇女,所以这是比较特殊的一类药物,显然任何毒性反应与很多人有关。目前倾向于减少孕激素或雌激素的含量,因此任何能降低这些低剂量制剂的生物利用度的因素都受到相当重视。本文主要陈述两个问题:甾体避孕药药物动力学与个体差异;药物的相互作用对避孕药效果的影响。 1.药物动力学血浆中甾体避孕药浓度的个体差异大,部分原因是代谢消除的速度不同引起的,例如6名受试者,取血样检验所服药物的半衰期各不相同。对炔诺酮,半衰期为6.1～12.3 Oral steroid contraceptives is one of the commonly used drugs in modern times. Most of the subjects are healthy women, so this is a rather special class of drugs, apparently any toxic reaction with many people. Currently, there is a tendency to reduce progestin or estrogen levels and therefore any factor that reduces the bioavailability of these low-dose formulations is of considerable importance. This article addresses two major issues: the pharmacokinetics and individual differences of steroid contraceptives; and the effect of drug interactions on the effectiveness of contraceptives. 1. Pharmacokinetics The individual differences in plasma concentrations of steroid contraceptives are large, in part because of differences in the rate of elimination of the metabolism, for example, six subjects, taking half-lives of drugs taken by the blood test. On norethindrone, the half-life of 6.1 ~ 12.3