allylestrenol 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. allylestrenolclinical datatrade namesgestanin, gestanon, perselin, turinal, othersother namesallyloestrenol; sc-6393; org al-25; 3-deketo-17α-allyl-19-nortestosterone; 17α-allylestr-4-en-17β-ol; 17α-(prop-2-en-1-yl)estr-4-en-17β-olpregnancycategory used in threatened miscarriage and recurrent pregnancy loss routes ofadministrationby mouthdrug classprogestogen; progestinatc codeg03dc01 (who) legal statuslegal status in general: ℞ (prescription only) pharmacokinetic dataprotein binding"considerable" (and low affinity for shbg)metabolismliver (reduction, hydroxylation, conjugation; cyp3a4)metabolites• 17α-allyl-19-ntelimination half-life"several hours" or 10 hoursexcretionurine (as conjugates)identifiers iupac name (8r,9s,10r,13s,14s,17r)-13-methyl-17-prop-2-enyl-2,3,6,7,8,9,10,11,12,14,15,16-dodecahydro-1h-cyclopentaphenanthren-17-ol cas number432-60-0 ypubchem cid235905drugbankdb01431 ychemspider205855 yuniii47vb5dz8okeggd01374 ychebichebi:31189 ychemblchembl2105618 ycomptox dashboard (epa)dtxsid9022574 echa infocard100.006.440 chemical and physical dataformulac21h32omolar mass300.486 g·mol−13d model (jsmol)interactive image smiles c12cc3(1cc2(cc=c)o)ccc4=cccc34 inchi inchi=1s/c21h32o/c1-3-12-21(22)14-11-19-18-9-8-15-6-4-5-7-16(15)17(18)10-13-20(19,21)2/h3,6,16-19,22h,1,4-5,7-14h2,2h3/t16-,17+,18+,19-,20-,21-/m0/s1 ykey:atxhvcqzzjymcf-xudstzeesa-n y (verify) 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. medical uses 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. on the other hand, allylestrenol was found to be effective in the treatment of hot flashes in postmenopausal women. allylestrenol has been commonly used in japan at high dosages, typically 50 mg/day but as much as 100 mg/day, to treat bph in men. related medications that have similarly been used to treat bph, particularly in japan, include chlormadinone acetate, gestonorone caproate, and oxendolone. allylestrenol has also been studied in the treatment of prostate cancer in japan. the medication has been studied as a puberty blocker in the treatment of precocious puberty as well. available forms allylestrenol is available in the form of 5 mg oral tablets. it is typically used at a dosage of 5 to 40 mg/day. in japan, a 25 mg allylestrenol oral tablet, under the brand name perselin, is marketed for the treatment of bph. side effects