Clostebol (INN; also known as 4-chlorotestosterone) usually as the ester clostebol acetate, is a synthetic anabolic–androgenic steroid (AAS). Clostebol is the 4-chloro derivative of the natural hormone testosterone. The chlorination prevents conversion to dihydrotestosterone (DHT) while also rendering the chemical incapable of conversion to estrogen.[citation needed] Although usually used as an ester including clostebol acetate (Macrobin, Steranabol, Alfa-Trofodermin, Megagrisevit), clostebol caproate (Macrobin-Depot), or clostebol propionate (Yonchlon), unmodified/non-esterified clostebol is also reported to be marketed, under the brand name Trofodermin-S in Mexico.[1]

Clostebol molecule ball.png
Clinical data
Other namesChlorotestosterone; 4-Chlorotestosterone; 4-Chloroandrost-4-en-17β-ol-3-one
Drug classAndrogen; Anabolic steroid
ATC code
  • None
Legal status
Legal status
CAS Number
PubChem CID
CompTox Dashboard (EPA)
ECHA InfoCard100.012.849 Edit this at Wikidata
Chemical and physical data
Molar mass322.87 g·mol−1
3D model (JSmol)
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Clostebol is a weak AAS with potential use as a performance enhancing drug. It is currently banned by the World Anti-Doping Agency.[2] Chlorodehydromethyltestosterone (Oral Turinabol), combining the chemical structures of clostebol and metandienone, was widely used in the East German state-sponsored doping program.[3]

Medical usesEdit

Clostebol acetate ointment has ophthalmological and dermatological use.[4]

Side effectsEdit


Clostebol, also known as 4-chlorotestosterone or as 4-chloroandrost-4-en-17β-ol-3-one, is a synthetic androstane steroid and a derivative of testosterone. It is specifically the 4-chlorinated derivative of testosterone.

Society and cultureEdit

Nutritional supplementsEdit

A related anabolic steroid, methylclostebol, is a common additive in so-called dietary supplements, generally listed in the convoluted form 4-chloro-17α-methyl-androst-4-en-17β-ol-3-one.[5]

Publicized abuse casesEdit

Use of clostebol has led to the suspension of a number of athletes in various sports including Freddy Galvis of the Philadelphia Phillies in 2012,[6] Dee Gordon of the Miami Marlins in 2016,[7] and Olympic athlete Viktoria Orsi Toth in 2016.[8]

In 2016, urinalysis resulted in Therese Johaug testing positive for clostebol.[9][10][11]


In the U.S., clostebol is listed as a Schedule III substance.[5]

See alsoEdit


  1. ^ Index Nominum 2000: International Drug Directory. Taylor & Francis. January 2000. pp. 265–. ISBN 978-3-88763-075-1.
  2. ^ "The World Anti-Doping Code: The 2020 Prohibited List" (PDF). World Anti-Doping Agency. Retrieved 2019-12-28.
  3. ^ "Doping for Gold: The State-Sponsored Doping Program". PBS. 2011-06-13.
  4. ^ Maccaroni E, Mele A, Del Rosso R, Malpezzi L (August 2011). "Clostebol acetate". Acta Crystallographica Section E. 67 (Pt 8): o1952-3. doi:10.1107/S1600536811026560. PMC 3212337. PMID 22090994.
  5. ^ a b Rahnema CD, Crosnoe LE, Kim ED (March 2015). "Designer steroids - over-the-counter supplements and their androgenic component: review of an increasing problem". Andrology. 3 (2): 150–5. doi:10.1111/andr.307. PMID 25684733. S2CID 6999218.
  6. ^ Breen M (July 11, 2016). "Phillies say they will welcome Stumpf back after drug suspension".
  7. ^ "Marlins 2B Dee Gordon suspended 80 games after PEDs violation". ESPN. 2016-04-29.
  8. ^ "Rio 2016, beach volley: conferma di doping per Viktoria Orsi Toth - Panorama" (in Italian). 2016-08-03. Retrieved 2016-08-03.
  9. ^ "Advokat: – Johaug fikk hele pakken". 2016-10-17.
  10. ^ "Slik hevder Johaug å ha fått i seg det forbudte stoffet". 2016-10-13.
  11. ^ "World's best cross-country skier Therese Johaug hit by new Norwegian doping scandal". October 13, 2016. Archived from the original on 2019-01-26. Retrieved 2016-10-18.