Stanazolol

Stanozolol

Clinical data
Trade names	Winstrol
AHFS/Drugs.com	Multum Consumer Information
Pregnancy category	X
Routes of administration	Oral, intramuscular injection
ATC code	A14AA02 (WHO)
Legal status
Legal status	CA: Schedule IV US: ℞-only
Pharmacokinetic data
Bioavailability	?
Metabolism	Hepatic
Biological half-life	1 day
Excretion	Renal: 84%
Identifiers
IUPAC name (1S,3aS,3bR,5aS,10aS,10bS,12aS)-1,10a,12a-trimethyl-1,2,3,3a,3b,4,5,5a,6,7,10,10a,10b,11,12,12a-hexadecahydrocyclopenta[5,6]naphtho[1,2-f]indazol-1-ol
Synonyms	17β-Hydroxy- 17α-methyl-5α-androstano[3,2-c]pyrazole
CAS Number	10418-03-8 Y
PubChem CID	25249
DrugBank	DB06718 Y
ChemSpider	23582 Y
UNII	4R1VB9P8V3
KEGG	D00444 Y
ChEBI	CHEBI:9249 N
ChEMBL	CHEMBL1200324 N
ECHA InfoCard	100.030.801
Chemical and physical data
Formula	C21H32N2O
Molar mass	328.49
3D model (Jmol)	Interactive image
SMILES O[C@@]5(C)CC[C@H]4[C@H]3[C@@H]([C@]2(Cc1c(nnc1)C[C@@H]2CC3)C)CC[C@@]45C
InChI InChI=1S/C21H32N2O/c1-19-11-13-12-22-23-18(13)10-14(19)4-5-15-16(19)6-8-20(2)17(15)7-9-21(20,3)24/h12,14-17,24H,4-11H2,1-3H3,(H,22,23)/t14-,15+,16-,17-,19-,20-,21-/m0/s1 Y Key:LKAJKIOFIWVMDJ-IYRCEVNGSA-N Y
NY (what is this?)

Stanozolol, commonly sold under the name Winstrol (oral) and Winstrol Depot (intramuscular), is a synthetic anabolic steroid derived from dihydrotestosterone. It was developed by American pharmaceutical company Winthrop Laboratories (Sterling Drug) in 1962, and has been approved by the FDA for human use.

Unlike most injectable anabolic steroids, stanozolol is not esterified and is sold as an aqueous suspension, or in oral tablet form. The drug has a high oral bioavailability, due to a C17 α-alkylation which allows the hormone to survive first-pass liver metabolism when ingested. It is because of this that stanozolol is also sold in tablet form.

Stanozolol has been used in both animal and human patients for a number of conditions. In humans, it has been demonstrated to be successful in treating anaemia and hereditary angioedema. Veterinarians may prescribe the drug to improve muscle growth, red blood cell production, increase bone density and stimulate the appetite of debilitated or weakened animals.

Stanozolol is one of the anabolic steroids commonly used as performance-enhancing drugs and is banned from use in sports competition under the auspices of the International Association of Athletics Federations (IAAF) and many other sporting bodies. Additionally, stanozolol has been used in US horse racing.

Stanozolol is subject to non-medically supervised off-label use by some athletes for its anabolic properties frequently presenting with concomitant reduction of body fat. Stanozolol is a modified derivative of dihydrotestosterone (DHT) and thus not aromatized to oestrogens via the aromatase class of enzymes (see chemical structure to right). Bodybuilders frequently misuse the term "dry" in describing their joint pain while using stanozolol either orally or via IM injection of an aqueous suspension; a reference to their perceived reason for an increase in joint pain. Rather, stanozolol as a DHT derivative can selectively compete with progesterone and other natural and synthetic progestins (nandrolone) for progestin receptors; yielding a reduction in progesterone mediated anti-inflammatory processes and presenting patients with a perception of increased joint discomfort.