Clinical and pharmacological group: Anti-climacteric estrogenic drug
Pharmaco-therapeutic group: Sex hormones and modulators of the reproductive system, natural and semi-synthetic estrogens
Pharmacological action
Estrogen, a means for replacement therapy. Estradiol valerate has a specific estrogenic effect: it causes proliferation of the endometrium, stimulates the development of the uterus and secondary female sexual characteristics when they are underdeveloped, alleviates and eliminates general disorders that occur in a woman’s body due to insufficient function of the sex glands during menopause or after gynecological operations.
Estradiol valerate maintains a balance between osteoblasts and osteoclasts, reduces bone resorption and promotes its formation.
Pharmacokinetics
After oral administration, estradiol valerate is quickly and completely absorbed from the gastrointestinal tract. Cmax of estradiol in blood plasma is achieved in 0.5 — 3 hours. Absolute bioavailability of estradiol is 3-5% of the oral dose of estradiol valerate. Plasma protein binding is 50%. Rapidly metabolized in the liver to form estriol and estrone. Subject to the «first pass» effect through the liver and to some extent — enterohepatic recirculation. Estradiol and its metabolites are excreted through the kidneys (mainly in the form of sulfates, glucuronides) and through the intestine in a ratio of 9:1. Within 5 days, 78-96% of the dose taken is excreted. T1 / 2 is about 27 hours.
