mestanolone mestanolone mestanolone, also known as methylandrostanolone and sold under the brand names androstalone and ermalone among others, is an androgen and anabolic steroid (aas) medication which is mostly no longer used. it is still available for use in japan however. it is taken by mouth. not to be confused with mesterolone. mestanoloneclinical datatrade namesandrostalone, ermalone, othersother namesru-143; methylandrostanolone; methyldihydrotestosterone; methyl-dht; 17α-methyl-4,5α-dihydrotestosterone; 17α-methyl-dht; 17α-methyl-5α-androstan-17β-ol-3-one;ahfs/drugs.cominternational drug namesroutes ofadministrationby mouthdrug classandrogen; anabolic steroidatc codenonelegal statuslegal status us: schedule iii pharmacokinetic datametabolismliverexcretionurineidentifiers iupac name (5s,8r,9s,10s,13s,14s,17s)-17-hydroxy-10,13,17-trimethyl-2,4,5,6,7,8,9,11,12,14,15,16-dodecahydro-1h-cyclopentaphenanthren-3-one cas number521-11-9 npubchem cid10633chemspider10187 yuniis712yz168ekeggd01533 ychemblchembl261514 ycomptox dashboard (epa)dtxsid0048973 echa infocard100.007.549 chemical and physical dataformulac20h32o2molar mass304.474 g·mol−13d model (jsmol)interactive image smiles o=c2c1cc3(1(c)cc2)cc4(3cc4(o)c)c inchi inchi=1s/c20h32o2/c1-18-9-6-14(21)12-13(18)4-5-15-16(18)7-10-19(2)17(15)8-11-20(19,3)22/h13,15-17,22h,4-12h2,1-3h3/t13-,15+,16-,17-,18-,19-,20-/m0/s1 ykey:wyzdxekuwrckob-ydsawkjfsa-n y ny (what is this?) (verify) side effects of mestanolone include symptoms of masculinization like acne, increased hair growth, voice changes, and increased sexual desire. it can also cause liver damage. the drug is a synthetic androgen and anabolic steroid and hence is an agonist of the androgen receptor (ar), the biological target of androgens like testosterone and dihydrotestosterone (dht). it has strong androgenic effects and weak anabolic effects, which make it useful for producing masculine psychological and behavioral effects. the drug has no estrogenic effects. mestanolone was discovered in 1935 and was introduced for medical use in the 1950s. in addition to its medical use, mestanolone has been used to improve physique and performance. it was used in east germany in olympic athletes as part of a state-sponsored doping program in the 1970s and 1980s. the drug is a controlled substance in many countries and so non-medical use is generally illicit. medical uses available forms mestanolone was available in the form of 25 mg sublingual tablets (brand name ermalone). pharmacology pharmacodynamics mestanolone is an aas, with both androgenic and anabolic effects. it is very similar in its effects to androstanolone (dihydrotestosterone; dht), and can be thought of as an orally active version of this aas. due to inactivation by 3α-hydroxysteroid dehydrogenase (3α-hsd) in skeletal muscle, mestanolone is described as a very poor anabolic agent, similarly to androstanolone and mesterolone. as mestanolone is 5α-reduced, it cannot be aromatized and hence has no propensity for estrogenic side effects such as gynecomastia. the drug also has no progestogenic activity. like other 17α-alkylated aas, mestanolone is hepatotoxic. pharmacokinetics due to its c17α methyl group, unlike androstanolone, mestanolone is orally active. chemistry