Allylestrenol

Allylestrenol, sold under the brand names Gestanin and Turinal among others, is a progestin medication which is used to treat recurrent and threatened miscarriage and to prevent premature labor in pregnant women. However, except in the case of proven progesterone deficiency, its use for such purposes is no longer recommended. It is also used in Japan to treat benign prostatic hyperplasia (BPH) in men. The medication is used alone and is not formulated in combination with an estrogen. It is taken by mouth. Side effects of allylestrenol are few and have not been well-defined, but are assumed to be similar to those of related medications. Allylestrenol is a progestin, or a synthetic progestogen, and hence is an agonist of the progesterone receptor, the biological target of progestogens like progesterone. It has no other important hormonal activity. The medication is a prodrug of 17α-allyl-19-nortestosterone (3-ketoallylestrenol) in the body. Allylestrenol was first described in 1958 and was introduced for medical use by 1961. It has been marketed widely throughout the world in the past, but today its availability and usage are relatively limited. It remains available in a few European countries and in a number of Asian countries. Allylestrenol is used in the treatment of recurrent and threatened miscarriage and to prevent premature labor. However, except in the case of proven progesterone deficiency, its use for such indications is no longer recommended. Allylestrenol is one of only a handful of progestogens that has commonly been used for such purposes, the others including progesterone, hydroxyprogesterone caproate, and dydrogesterone. The medication has also been studied in the treatment of gynecological disorders such as amenorrhea, irregular menstruation, and premenstrual syndrome. Unlike other progestins, allylestrenol has not been used in hormonal contraception or in menopausal hormone therapy. In one study, it was found to be inadequate for endometrial transformation in women in combination with estradiol valerate.