Hormonal Oestrogens, conjugated

Ethinyloestradiol, or its methylated derivative mestranol, is a satisfactory first choice for pharmacotherapy. The weaker endogenous oestrogens, oestradiol, oestrone or the conjugated equine oestrogens are preferable for physiological replacement. It remains uncertain whether all oestrogens have exactly similar hormonal and nonhormonal effects, including adverse effects. 

Conjugated oestrogenic hormone Premarin Hormone replacement therapy 14804... 

Levonorgestrel is metabolised to inactive substances before it is conjugated, and does not therefore undergo enterohepatic recycling of the active moiety. There is no reason to expect that its efficacy as an emergency contraceptive would be affected by antibacterials that alter gut flora and do not induce liver enzymes. No special precautions are necessary with these antibacterials. However, rifampicin and rifabutin are likely to reduce the efficacy of most forms of hormonal contraceptives, as they induce the metabolism of oestrogens and progestagens, see Hormonal contraceptives + Rifamycins , p. 1001. 

A full account of the further metabolism and conjugation of steroid hormones is beyond the scope of this chapter, but a few remarks might be germane. Oestrogens can be transformed into the corresponding glycosides, sul-... 

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