Stanozolol

{{Short description|Discontinued steroid for heart treatment}} {{Distinguish|Androstanolone{{!}}Stanolone|Isoniazid{{!}}Stanozide|Trilostane{{!}}Winstan}} {{cs1 config|name-list-style=vanc|display-authors=6}} {{Infobox drug | Verifiedfields = verified | Watchedfields = verified | verifiedrevid = 470470548 | image = Stanozolol.svg | image_class = skin-invert-image | width = 250px | imageL = Estanozolol-3D.png | image_classL = bg-transparent | widthL = 125px | imageR = Estanozolol-3D-CPK.png | image_classR = bg-transparent | widthR = 125px | 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

| tradename = Winstrol, Stromba, others<ref name="Drugs.com" /> | Drugs.com = {{drugs.com|MTM|winstrol}} | pregnancy_category = X | legal_BR = C5 | legal_BR_comment = <ref>{{Cite web |author=Anvisa |author-link=Brazilian Health Regulatory Agency |date=2023-03-31 |title=RDC Nº 784 - Listas de Substâncias Entorpecentes, Psicotrópicas, Precursoras e Outras sob Controle Especial |trans-title=Collegiate Board Resolution No. 784 - Lists of Narcotic, Psychotropic, Precursor, and Other Substances under Special Control|url=https://www.in.gov.br/en/web/dou/-/resolucao-rdc-n-784-de-31-de-marco-de-2023-474904992 |url-status=live |archive-url=https://web.archive.org/web/20230803143925/https://www.in.gov.br/en/web/dou/-/resolucao-rdc-n-784-de-31-de-marco-de-2023-474904992 |archive-date=2023-08-03 |access-date=2023-08-15 |publisher=Diário Oficial da União |language=pt-BR |publication-date=2023-04-04}}</ref> | legal_CA = Schedule IV | legal_US = Schedule III | legal_status = Rx only | routes_of_administration = By mouth, intramuscular injection (veterinary)<ref name="Thieme_2009" /> | class = Androgen; Anabolic steroid

| bioavailability = High<ref name="Maini_2014">{{cite journal | vauthors = Maini AA, Maxwell-Scott H, Marks DJ | title = Severe alkalosis and hypokalemia with stanozolol misuse | journal = The American Journal of Emergency Medicine | volume = 32 | issue = 2 | pages = 196.e3–196.e4 | date = February 2014 | pmid = 24521609 | doi = 10.1016/j.ajem.2013.09.027 | quote = This case is important as stanozolol misuse is relatively common, due to its high oral bioavailability and perceived safety profile compared with other parenteral AAS. }}</ref> | protein_bound = | metabolism = Liver<ref name="Hsu_2013" /> | elimination_half-life = Oral: 9 hours<ref name="Ruiz_2011">{{cite book | vauthors = Ruiz P, Strain EC | title = Lowinson and Ruiz's Substance Abuse: A Comprehensive Textbook | pages = 358– | year = 2011 | url = https://books.google.com/books?id=w4ZUJAdleTsC&pg=PA358 | publisher = Lippincott Williams & Wilkins | isbn = 978-1-60547-277-5 }}</ref><br />{{abbrlink|IM|Intramuscular injection}}: 24 hours ({{abbr|aq. susp.|aqueous suspension}})<ref name="Ruiz_2011" /><ref name="Thieme_2009" /> | duration_of_action = {{abbr|IM|Intramuscular injection}}: >1 week<ref name="Hsu_2013">{{cite book | vauthors = Hsu WH | title = Handbook of Veterinary Pharmacology | pages = 404– | date = 25 April 2013 | url = https://books.google.com/books?id=MGhScg9GZGAC&pg=PT404 | publisher = John Wiley & Sons | isbn = 978-1-118-71416-4 }}</ref> | excretion = Urine: 84%{{Citation needed|date=April 2018}}

| CAS_number_Ref = {{cascite|correct|CAS}} | CAS_number = 10418-03-8 | ATC_prefix = A14 | ATC_suffix = AA02 | PubChem = 25249 | DrugBank_Ref = {{drugbankcite|correct|drugbank}} | DrugBank = DB06718 | ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}} | ChemSpiderID = 23582 | ChEBI_Ref = {{ebicite|correct|EBI}} | ChEBI = 9249 | IUPHAR_ligand = 10369 | UNII_Ref = {{fdacite|correct|FDA}} | UNII = 4R1VB9P8V3 | KEGG_Ref = {{keggcite|correct|kegg}} | KEGG = D00444 | ChEMBL_Ref = {{ebicite|correct|EBI}} | ChEMBL = 2079587 | synonyms = Androstanazol; Androstanazole; Stanazol; WIN-14833; NSC-43193; NSC-233046; 17α-Methyl-2<nowiki>'</nowiki>''H''-5α-androst-2-eno[3,2-''c'']pyrazol-17β-ol; 17α-Methylpyrazolo[4',3':2,3]-5α-androstan-17β-ol

| C=21 | H=32 | N=2 | O=1 | SMILES = [H][C@@]35CC[C@@]2([H])[C@]1([H])CC[C@](C)(O)[C@@]1(C)CC[C@]2([H])[C@@]3(C)Cc4c[nH]nc4C5 | StdInChI_Ref = {{stdinchicite|correct|chemspider}} | StdInChI = 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 | StdInChIKey_Ref = {{stdinchicite|correct|chemspider}} | StdInChIKey = LKAJKIOFIWVMDJ-IYRCEVNGSA-N }}

'''Stanozolol''' (abbrev. '''Stz'''), sold under many brand names, is a synthetic androgen and anabolic steroid (AAS) medication derived from dihydrotestosterone (DHT). It is used to treat hereditary angioedema.<ref name="IndexNominum2000">{{cite book | title = Index Nominum 2000: International Drug Directory | pages = 961– | year = 2000 | url = https://books.google.com/books?id=5GpcTQD_L2oC&pg=PA961 | publisher = Taylor & Francis | isbn = 978-3-88763-075-1 }}</ref><ref name="Drugs.com">{{cite web | title = Stanozolol - Drugs.com | url = https://www.drugs.com/international/stanozolol.html }}</ref><ref name="Llewellyn_2011">{{cite book | vauthors = Llewellyn W | title = Anabolics | pages = 726–737 | year = 2011 | url = https://books.google.com/books?id=afKLA-6wW0oC&pg=PT726 | publisher = Molecular Nutrition Llc | isbn = 978-0-9828280-1-4 }}</ref> It was developed by American pharmaceutical company Sterling-Winthrop in 1962, and has been approved by the U.S. Food and Drug Administration for human use, though it is no longer marketed in the United States.<ref name="Llewellyn_2011" /><ref name="Drugs@FDA">{{Cite web | title = Drugs@FDA: FDA Approved Drug Products | url = https://www.accessdata.fda.gov/scripts/cder/daf/ | website = www.accessdata.fda.gov | access-date = 2016-02-18 }}</ref> It is also used in veterinary medicine.<ref name="Drugs.com" /><ref name="Llewellyn_2011" /> Stanozolol has mostly been discontinued, and remains available in only a few countries.<ref name="Drugs.com" /><ref name="Llewellyn_2011" /> It is given by mouth in humans or by injection into muscle in animals.<ref name="Llewellyn_2011" />

Unlike most AAS, stanozolol is not esterified and is sold as an aqueous suspension, or in oral tablet form.<ref name="Llewellyn_2011" /> The drug has a high oral bioavailability, due to a C17α alkylation which allows the hormone to survive first-pass liver metabolism when ingested.<ref>{{Cite web | title = stanozolol (CHEBI:9249) | url = https://www.ebi.ac.uk/chebi/searchId.do?printerFriendlyView=true&locale=null&chebiId=9249&viewTermLineage=null&structureView=&#:~:text=Unlike%20most%20injectable%20AAS,%20stanozolol,pass%20liver%20metabolism%20when%20ingested. | access-date = 2020-09-06 | website = www.ebi.ac.uk }}</ref><ref name="Llewellyn_2011" /> It is because of this that stanozolol is also sold in tablet form.<ref name="Llewellyn_2011" />

Stanozolol is one of the AAS commonly used as performance-enhancing drugs and is banned from use in sports competition under the auspices of the World Anti-Doping Agency (WADA). It is an anabolic steroid that is known to have a diuretic effect. Additionally, stanozolol has been highly restricted in US horse racing.<ref>{{Cite web | title = Anabolic Steroids Still an Issue in U.S. Horse Racing | date = 2015-02-13 | url = https://thehorse.com/111400/anabolic-steroids-still-an-issue-in-u-s-horse-racing/ | access-date = 2020-09-06 | website = The Horse }}</ref><ref>{{cite web | title = Win, Place, and Dope | date = 1 May 2009 | url = http://www.slate.com/id/2217357/ | work = Slate }}</ref><ref>{{cite web | title = Model Rules Ver 9.5 | last1 = Anonymous | url = https://www.arci.com/model-rules-standards/ | website = ARCI.com | publisher = ARCI | access-date = 2021-03-14 | archive-date = 2021-06-03 | archive-url = https://web.archive.org/web/20210603164359/https://www.arci.com/model-rules-standards/ | url-status = dead }}</ref>

==Medical uses== Stanozolol has been used with some success to treat venous insufficiency. It stimulates blood fibrinolysis and has been evaluated for the treatment of the more advanced skin changes in venous disease such as lipodermatosclerosis. Several randomized trials noted improvement in the area of lipodermatosclerosis, reduced skin thickness, and possibly faster ulcer healing rates with stanozolol.<ref>{{cite journal | vauthors = Burnand K, Clemenson G, Morland M, Jarrett PE, Browse NL | title = Venous lipodermatosclerosis: treatment by fibrinolytic enhancement and elastic compression | journal = British Medical Journal | volume = 280 | issue = 6206 | pages = 7–11 | date = January 1980 | pmid = 6986945 | pmc = 1600523 | doi = 10.1136/bmj.280.6206.7 }}</ref><ref>{{cite journal | vauthors = McMullin GM, Watkin GT, Coleridge Smith PD, Scurr JH | title = Efficacy of fibrinolytic enhancement with stanozolol in the treatment of venous insufficiency | journal = The Australian and New Zealand Journal of Surgery | volume = 61 | issue = 4 | pages = 306–309 | date = April 1991 | pmid = 2018441 | doi = 10.1111/j.1445-2197.1991.tb00217.x }}</ref> It is also being studied to treat hereditary angioedema, osteoporosis, and skeletal muscle injury.<ref>{{cite journal | vauthors = Sloane DE, Lee CW, Sheffer AL | title = Hereditary angioedema: Safety of long-term stanozolol therapy | journal = The Journal of Allergy and Clinical Immunology | volume = 120 | issue = 3 | pages = 654–658 | date = September 2007 | pmid = 17765757 | doi = 10.1016/j.jaci.2007.06.037 | doi-access = free }}</ref><ref name="Tingus_1993">{{cite journal | vauthors = Tingus SJ, Carlsen RC | title = Effect of continuous infusion of an anabolic steroid on murine skeletal muscle | journal = Medicine and Science in Sports and Exercise | volume = 25 | issue = 4 | pages = 485–494 | date = April 1993 | pmid = 8479303 }}</ref>

==Non-medical uses== Stanozolol is used for physique- and performance-enhancing purposes by competitive athletes, bodybuilders, and powerlifters.<ref name="Llewellyn_2011" />

==Side effects== {{See also|Anabolic steroid#Adverse effects}}

Side effects of stanozolol include virilization (masculinization), hepatotoxicity,<ref name="Llewellyn_2011" /> cardiovascular disease, and hypertension.

==Pharmacology==

===Pharmacodynamics=== {{Relative androgenic to anabolic activity in animals}}

As an AAS, stanozolol is an agonist of the androgen receptor (AR), similarly to androgens like testosterone and DHT.<ref name="Llewellyn_2011" /><ref name="Kicman_2008">{{cite journal | vauthors = Kicman AT | title = Pharmacology of anabolic steroids | journal = British Journal of Pharmacology | volume = 154 | issue = 3 | pages = 502–521 | date = June 2008 | pmid = 18500378 | pmc = 2439524 | doi = 10.1038/bjp.2008.165 }}</ref> Its affinity for the androgen receptor is about 22% of that of dihydrotestosterone.<ref name="Doods_1991">{{cite book | vauthors = Doods HN | title = Receptor Data for Biological Experiments: A Guide to Drug Selectivity | pages = 250 | year = 1991 | url = https://books.google.com/books?id=2_l8AAAAIAAJ | publisher = Ellis Horwood | isbn = 978-0-13-767450-3 }}</ref> Stanozolol is not a substrate for 5α-reductase as it is already 5α-reduced, and so is not potentiated in so-called "androgenic" tissues like the skin, hair follicles, and prostate gland.<ref name="Llewellyn_2011" /><ref name="Kicman_2008" /> This results in a greater ratio of anabolic to androgenic activity compared to testosterone.<ref name="Llewellyn_2011" /><ref name="Kicman_2008" /> In addition, due to its 5α-reduced nature, stanozolol is non-aromatizable, and hence has no propensity for producing estrogenic effects such as gynecomastia or fluid retention.<ref name="Llewellyn_2011" /><ref name="Kicman_2008" /> Stanozolol also does not possess any progestogenic activity of significance.<ref name="Llewellyn_2011" /><ref name="Kicman_2008" /> Because of the presence of its 17α-methyl group, the metabolism of stanozolol is sterically hindered, resulting in it being orally active, although also hepatotoxic.<ref name="Llewellyn_2011" /><ref name="Kicman_2008" />

;Multi-receptor activity and stem-cell differentiation In addition to classical AR signaling, ''in-vitro'' work with mesenchymal stem-cell micromass cultures shows that stanozolol:

* Binds to the progesterone receptor (PR) and to an unidentified membrane receptor that drives Prostaglandin E2 (PGE₂) synthesis via COX-2 induction.<ref name="Mori_2020">{{cite thesis | vauthors = Mori D | title = The role of stanozolol in the stimulation of cellular mechanisms for osteochondral regeneration | year = 2020 | type = PhD thesis | publisher = Università di Parma | url = https://www.repository.unipr.it/bitstream/1889/4372/1/tesi%20Daniele%20Mori.pdf }}</ref> * Induces a feed-forward loop in which PGE₂ amplifies BMP2 expression, accelerating osteogenic and chondrogenic differentiation.<ref name="Mori_2020" /> * Causes sustained phosphorylation of PKCε, an isoform linked to suppression of the hypertrophic cartilage marker MATN1 and to formation of articular-cartilage (interzone) phenotypes.<ref name="Mori_2020" />

Pharmacological blockade of either PR (mifepristone) or COX-2 (indomethacin) abolishes these effects, confirming that stanozolol’s osteochondral activity requires simultaneous PR signaling and PGE₂-driven crosstalk with the BMP2 pathway.<ref name="Mori_2020" />

Additionally, stanozolol has been shown to exert activity via estrogen receptor alpha (ERα) in vivo. In a rat model of GnRH agonist-induced growth plate suppression, stanozolol restored chondrocyte proliferation via ERα activation, indicating selective estrogen receptor-mediated effects in growth plate cartilage.<ref name="Zhu_2011">{{cite journal | vauthors = Zhu S, Li Y, Ma H, Huang T, Luo H, Dou J, Du M | title = Stanozolol regulates proliferation of growth plate chondrocytes via activation of ERα in GnRHa-treated adolescent rats | journal = J Pediatr Endocr Met | volume = 24 | issue = 5–6 | pages = 275–281 | year = 2011 | pmid = 21823523 | doi = 10.1515/jpem.2011.183 }}</ref>

===Pharmacokinetics=== Stanozolol has high oral bioavailability, due to the presence of its C17α alkyl group and the resistance to gastrointestinal and liver metabolism that it results in.<ref name="Maini_2014" /><ref name="Bilezikian_2002">{{cite book | vauthors = Bilezikian JP, Raisz LG, Rodan GA | title = Principles of Bone Biology, Two-Volume Set | pages = 1455– | date = 19 January 2002 | url = https://books.google.com/books?id=jcvh_okaAk8C&pg=PA1455 | publisher = Academic Press | isbn = 978-0-08-053960-7 | quote = Androgenic compounds rendered resistant to gastrointestinal and liver metabolism by containing an alkyl group at the C17α position, such as stanozolol, are orally active. }}</ref><ref name="Herron_2015">{{cite book | vauthors = Herron A, Brennan TK | title = The ASAM Essentials of Addiction Medicine | pages = 262– | date = 18 March 2015 | url = https://books.google.com/books?id=vjFzBwAAQBAJ&pg=PT262 | publisher = Wolters Kluwer Health | isbn = 978-1-4963-1067-5 | quote = Testosterone has low oral bioavailability with only about half of an oral dose available after hepatic first-pass metabolism. Some analogues of testosterone (e.g., methyltestosterone, fluoxymesterone, oxandrolone, and stanozolol) resist such metabolism, so they can be given orally in smaller doses. }}</ref> The medication has very low affinity for human serum sex hormone-binding globulin (SHBG), about 5% of that of testosterone and 1% of that of DHT.<ref name="Saartok_1984">{{cite journal | vauthors = Saartok T, Dahlberg E, Gustafsson JA | title = Relative binding affinity of anabolic-androgenic steroids: comparison of the binding to the androgen receptors in skeletal muscle and in prostate, as well as to sex hormone-binding globulin | journal = Endocrinology | volume = 114 | issue = 6 | pages = 2100–2106 | date = June 1984 | pmid = 6539197 | doi = 10.1210/endo-114-6-2100 }}</ref> Stanozolol is metabolized in the liver, ultimately becoming glucuronide and sulfate conjugates.<ref name="Hsu_2013" /> Its biological half-life is reported to be 9 hours when taken by mouth and 24 hours when given by intramuscular injection in the form of an aqueous suspension.<ref name="Ruiz_2011" /><ref name="Thieme_2009">{{cite book | vauthors = Thieme D, Hemmersbach P | title = Doping in Sports | pages = 166– | date = 18 December 2009 | url = https://books.google.com/books?id=R-hIC-caIn8C&pg=PA166 | publisher = Springer Science & Business Media | isbn = 978-3-540-79088-4 | quote = The oral form is marketed for human use whereas an aqueous suspension for injection is used in the veterinary field. }}</ref> It is said to have a duration of action of one week or more via intramuscular injection.<ref name="Hsu_2013" />

==Chemistry== {{See also|List of androgens/anabolic steroids}}

Stanozolol, also known as 17α-methyl-2<nowiki>'</nowiki>''H''-androst-2-eno[3,2-''c'']pyrazol-17β-ol, is a synthetic 17α-alkylated androstane steroid and a derivative of 5α-dihydrotestosterone (DHT) with a methyl group at the C17α position and a pyrazole ring attached to the A ring of the steroid nucleus.<ref name="IndexNominum2000" />

===Synthesis=== Various chemical syntheses of stanozolol have been published.<ref name="Publishing2013">{{cite book | title = Pharmaceutical Manufacturing Encyclopedia | pages = 3067– | date = 22 October 2013 | url = https://books.google.com/books?id=_J2ti4EkYpkC&pg=PA3067 | publisher = Elsevier | isbn = 978-0-8155-1856-3 }}</ref>

===Detection in body fluids=== Stanozolol is subject to extensive hepatic biotransformation by a variety of enzymatic pathways. The primary metabolites are unique to stanozolol and are detectable in the urine for up to 10 days after a single 5–10 mg oral dose. Methods for detection in urine specimens usually involve gas chromatography-mass spectrometry or liquid chromatography-mass spectrometry.<ref>{{cite journal | vauthors = Mateus-Avois L, Mangin P, Saugy M | title = Use of ion trap gas chromatography-multiple mass spectrometry for the detection and confirmation of 3'hydroxystanozolol at trace levels in urine for doping control | journal = Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences | volume = 816 | issue = 1–2 | pages = 193–201 | date = February 2005 | pmid = 15664350 | doi = 10.1016/j.jchromb.2004.11.033 }}</ref><ref>{{cite journal | vauthors = Pozo OJ, Van Eenoo P, Deventer K, Lootens L, Grimalt S, Sancho JV, Hernández F, Meuleman P, Leroux-Roels G, Delbeke FT | title = Detection and structural investigation of metabolites of stanozolol in human urine by liquid chromatography tandem mass spectrometry | journal = Steroids | volume = 74 | issue = 10–11 | pages = 837–852 | date = October 2009 | pmid = 19464304 | doi = 10.1016/j.steroids.2009.05.004 | s2cid = 36617387 }}</ref><ref>{{cite book | vauthors = Baselt R | title = Disposition of Toxic Drugs and Chemicals in Man | location = Foster City, CA | pages = 1442–1443 | year = 2008 | edition = 8th | publisher = Biomedical Publications }}</ref>

==History== In 1962, Stanozolol was brought to market in the US by Winthrop under the tradename "Winstrol" and in Europe by Winthrop's partner, Bayer, under the name "Stromba".<ref name="Levin_1962">{{cite journal | vauthors = Levin J, Trafford JA, Bishop PM | title = Stanozolol, a new anabolic steroid | journal = The Journal of New Drugs | volume = 2 | pages = 50–55 | date = 1962 | pmid = 14464563 | doi = 10.1177/009127006200200106 | s2cid = 10993184 }}</ref>

Also in 1962, the Kefauver Harris Amendment was passed, amending the Federal Food, Drug, and Cosmetic Act to require drug manufacturers to provide proof of the effectiveness of their drugs before approval.<ref>{{cite web | title = Promoting Safe and Effective Drugs for 100 Years | url = https://www.fda.gov/AboutFDA/WhatWeDo/History/CentennialofFDA/CentennialEditionofFDAConsumer/ucm093787.htm | archive-url = https://web.archive.org/web/20090709193833/http://www.fda.gov/AboutFDA/WhatWeDo/History/CentennialofFDA/CentennialEditionofFDAConsumer/ucm093787.htm | url-status = dead | archive-date = July 9, 2009 | work = The Kefauver-Harris Drug Amendments | publisher = U.S. Food and Drug Administration }}</ref> The FDA implemented its Drug Efficacy Study Implementation (DESI) program to study and regulate drugs, including stanozolol, that had been introduced prior to the amendment. The DESI program was intended to classify all pre-1962 drugs that were already on the market as effective, ineffective, or needing further study.<ref>{{cite web | title = FDA aims to remove unapproved drugs from market: Risk-based enforcement program focuses on removing potentially harmful products | date = August 2008 | work = Pharmacy Today | url = https://www.fda.gov/downloads/drugs/guidancecomplianceregulatoryinformation/enforcementactivitiesbyfda/selectedenforcementactionsonunapproveddrugs/ucm119899.pdf | archive-url = https://web.archive.org/web/20090710143208/http://www.fda.gov/downloads/Drugs/GuidanceComplianceRegulatoryInformation/EnforcementActivitiesbyFDA/SelectedEnforcementActionsonUnapprovedDrugs/ucm119899.pdf | url-status = dead | archive-date = July 10, 2009 | publisher = United States Food and Drug Administration }}</ref> The FDA enlisted the National Research Council of the National Academy of Sciences to evaluate publications on relevant drugs under the DESI program.<ref>{{cite web | title = The Drug Efficacy Study of the National Research Council's Division of Medical Sciences, 1966-1969 | work = National Academies of Sciences archives. | url = http://www.nasonline.org/about-nas/history/archives/collections/des-1966-1969-1.html }}</ref>

In June 1970 the FDA announced its conclusions on the effectiveness of certain AAS, including stanozolol, based on the NAS/NRC reports made under DESI. The drugs were classified as probably effective as adjunctive therapy in the treatment of senile and postmenopausal osteoporosis but only as an adjunct, and in pituitary dwarfism (with a specific caveat for dwarfism, "until growth hormone is more available"), and as lacking substantial evidence of effectiveness for several other indications. Specifically, the FDA found a lack of efficacy for stanozolol as "an adjunct to promote body tissue-building processes and to reverse tissue-depleting processes in such conditions as malignant diseases and chronic nonmalignant diseases; debility in elderly patients, and other emaciating diseases; gastrointestinal disorders resulting in alterations of normal metabolism; use during pre-operative and postoperative periods in undernourished patients and poor-risk surgical cases due to traumatism; use in infants, children, and adolescents who do not reach an adequate weight; supportive treatment to help restore or maintain a favorable metabolic balance, as in postsurgical, postinfectious, and convalescent patients; of value in pre- operative patients who have lost tissue from a disease process or who have associated symptoms, such as anorexia; retention and utilization of calcium; surgical applications; gastrointestinal disease, malnourished adults, and chronic illness; pediatric nutritional problems; prostatic carcinoma; and endocrine deficiencies."<ref name="FedReg1970">{{cite journal | title = Food and Drug Administration Notice.DESI 7630. Certain Anabolic Steroids. Drugs for Human Use: Drug Efficacy Study Implementation | journal = Federal Register | volume = 35 | issue = 122 | pages = 10327–10328 | date = 24 June 1970 | url = https://archive.org/details/federalregister35cunit }}</ref> The FDA gave Sterling six months to stop marketing stanozolol for the indications for which there was no evidence for efficacy, and one year to submit further data for the two indications for which it found probable efficacy.<ref name="FedReg1970" />

In August and September 1970, Sterling submitted more data; the data was not sufficient but the FDA allowed the drug to continue to be marketed, since there was an unmet need for drugs for osteoporosis and pituitary dwarfism, but Sterling was required to submit more data.<ref name=FedReg1984>Food and Drug Administration Notice. Docket No 80N-0276; DESI 7630. Winstrol Tablets; Drugs for Human Use; Drug Efficacy Study Implementation, Revocation of Exemption; Followup Notice and Opportunity for Hearing on Proposal to Withdraw Approval of New Drug [https://archive.org/details/federalregister49eunit Federal Register, April 23, 1984]. page 17094-99</ref>

In 1980 the FDA removed the dwarfism indication from the label for stanozolol since human growth hormone drugs had come on the market, and mandated that the label for stanozolol and other steroids say: "As adjunctive therapy in senile and postmenopausal osteoporosis. AAS are without value as primary therapy but may be of value as adjunctive therapy. Equal or greater consideration should be given to diet, calcium balance, physiotherapy, and good general health promoting measures." and gave Sterling a timeline to submit further data for other indications it wanted for the drug.<ref name="FedReg1980">Food and Drug Administration Notice. Docket No 80N-0276; Drugs for Human Use; Drug Efficacy Study Implementation; Conditions for Continued Marketing of Anabolic Steroids for Treatment [https://archive.org/details/federalregister45runit Federal Register Vol 45 No. 213. October 31 1980]. pages 72291-93</ref> Sterling submitted data to the FDA intended to support the effectiveness of Winstrol for postmenopausal osteoporosis and aplastic anemia in December, 1980 and August 1983 respectively. The FDA's Endocrinologic and Metabolic Drugs Advisory Committee considered the data submitted for osteoporosis in two meetings held 1981 and the data for aplastic anemia in 1983.<ref name="FedReg1984" />

In April 1984, the FDA announced that the data was not sufficient, and withdrew the marketing authority for stanozolol for senile and postmenopausal osteoporosis and for raising hemoglobin levels in aplastic anemia.<ref name="FedReg1984" /><ref>The Pink Sheet 30 April 1984 [https://www.pharmamedtechbi.com/publications/the-pink-sheet/46/018/sterling-winstrol-stanozolol-nda-withdrawal-process-beginning-fda Sterling Winstrol (Stanozolol) NDA Withdrawal Process Beginning, FDA]</ref>

In 1988, Sterling was acquired by Eastman Kodak for $5.1 billion and in 1994 Kodak sold the drug business of Sterling to Sanofi for $1.675 billion.<ref name="Collins_2000">{{cite journal | vauthors = Collins JC, Gwilt JR | title = The Life Cycle of Sterling Drug, Inc. | journal = Bull. Hist. Chem. | volume = 25 | issue = 1 | date = 2000 | url = http://www.scs.illinois.edu/~mainzv/HIST/bulletin_open_access/v25-1/v25-1%20p22-27.pdf }}</ref><ref name="LAT62494">{{cite news | title = Kodak to Sell Drug Unit for $1.68 Billion | date = June 24, 1994 | url = https://www.latimes.com/archives/la-xpm-1994-06-24-fi-8107-story.html | access-date = 3 May 2013 | newspaper = Los Angeles Times }}</ref>

Sanofi had stanozolol manufactured in the US by Searle, which stopped making the drug in October 2002.<ref>{{cite web | title = Products | publisher = Ovation Pharmaceuticals | url = http://www.ovationpharma.com/products.html | archive-url = https://web.archive.org/web/20040110181418/http://www.ovationpharma.com/products.html | url-status = dead | archive-date = 2004-01-10 }}</ref> Even with no drug in production, Sanofi sold the stanozolol business to Ovation Pharmaceuticals in 2003, along with the two other drugs.<ref name="Ovationsale">{{cite web | title = Press release: Ovation Pharmaceuticals Acquires Mebaral(R), Chemet(R), and Winstrol(R) From Sanofi-Synthelabo Inc. | date = 7 August 2003 | work = PRnewswire | url = http://www.prnewswire.com/news-releases/ovation-pharmaceuticals-acquires-mebaralr-chemetr-and-winstrolr-from-sanofi-synthelabo-inc-70900312.html }}</ref> At that time, the drug had not been discontinued and was considered a treatment for hereditary angioedema.<ref name="Ovationsale" /> In March 2009, Lundbeck purchased Ovation<ref>{{cite web | title = Press Release: GTCR Completes the Sale of Ovation Pharmaceuticals to Lundbeck | date = 19 March 2009 | work = Reuters | url = https://www.reuters.com/article/2009/03/19/idUS126648+19-Mar-2009+BW20090319 | archive-url = https://web.archive.org/web/20110220110255/http://www.reuters.com/article/2009/03/19/idUS126648+19-Mar-2009+BW20090319 | url-status = dead | archive-date = 20 February 2011 }}</ref>

In 2010, Lundbeck withdrew stanozolol from the market in the US; as of 2014 no other company is marketing stanozolol as a pharmaceutical drug in the US but it can be obtained via a compounding pharmacy.<ref>{{cite web | title = Novartis Pharmaceuticals Corp. et al.; Withdrawal of Approval of 27 New Drug Applications and 58 Abbreviated New Drug Applications | date = 21 July 2010 | url = https://www.federalregister.gov/articles/2010/07/21/2010-17785/novartis-pharmaceuticals-corp-et-al-withdrawal-of-approval-of-27-new-drug-applications-and-58  }}</ref><ref name="OrangeBook">FDA [https://web.archive.org/web/20060925233657/http://www.accessdata.fda.gov/scripts/cder/drugsatfda/index.cfm?fuseaction=Search.Overview&DrugName=WINSTROL Drugs@FDA: Stanozolol]</ref><ref name="HAEA" /><ref name="Craig_2012" />

Pfizer had marketed stanozolol as a veterinary drug; in 2013 Pfizer spun off its veterinary business to Zoetis<ref>Zoetis. 24 June 2013 [http://news.zoetis.com/press-release/corporate/zoetis-becomes-fully-independent-acceptance-pfizer-shares-tendered-exchange-#sthash.ndOBmznm.dpuf Zoetis Press Release: Zoetis Becomes Fully Independent With Acceptance of Pfizer Shares Tendered in Exchange Offer] {{Webarchive|url=https://web.archive.org/web/20141129103815/http://news.zoetis.com/press-release/corporate/zoetis-becomes-fully-independent-acceptance-pfizer-shares-tendered-exchange-#sthash.ndOBmznm.dpuf |date=2014-11-29 }}</ref> and in 2014 Pfizer transferred the authorizations to market injectable and tablet forms of stanozolol as a veterinary drug to Zoetis.<ref>{{cite web  | title = Implantation or Injectable Dosage Form New Animal Drugs; Change of Sponsor | date = 20 May 2014 | work = Federal Register | url = https://www.federalregister.gov/articles/2014/03/25/2014-06131/implantation-or-injectable-dosage-form-new-animal-drugs-change-of-sponsor }}</ref><ref>{{cite web | title = Oral Dosage Form New Animal Drugs; Change of Sponsor | date = 25 March 2014 | work = A Rule by the Food and Drug Administration | publisher = Federal Register | url = https://www.federalregister.gov/articles/2014/05/20/2014-10415/oral-dosage-form-new-animal-drugs-change-of-sponsor }}</ref>

It is used in veterinary medicine as an adjunct in the management of wasting diseases, to stimulate the formation of red blood cells, arouse appetite, and promote weight gain, but the evidence for these uses is weak. It is used as a performance-enhancing drug in race horses. Its side effects include weight gain, water retention, and difficulty eliminating nitrogen-based waste products and it is toxic to the liver, especially in cats. Because it may promote the growth of tumors, it is contraindicated in dogs with enlarged prostates.<ref>{{cite book | vauthors = Riviere JE, Papich MG | title = Veterinary Pharmacology and Therapeutics | date = 2013 | publisher = John Wiley & Sons | isbn = 978-1-118-68590-7 }}</ref>{{rp|730-371}}

Stanozolol and other AAS were commonly used to treat hereditary angioedema attacks, until several drugs were brought to market specifically for treatment of that disease, the first in 2009: Cinryze, Berinert, ecallantide (Kalbitor), icatibant (Firazyr) and Ruconest.<ref name="HAEA">The US Hereditary Angioedema Association [http://www.haea.org/patients/treatments/ Treatments]</ref><ref name="Craig_2012">{{cite web | vauthors = Craig TJ, Kalra N | title = Contemporary Issues in Prophylactic Therapy of Hereditary Angioedema | date = 30 July 2012 | work = MedScape Education | url = http://www.medscape.org/viewarticle/729693 }}</ref> Stanozolol is still used long-term to reduce the frequency of severity of attacks.<ref>{{cite book | vauthors = Delves PJ | chapter = Hereditary and Acquired Angioedema | title = Merck Manual | date = March 2014 | chapter-url = http://www.merckmanuals.com/professional/immunology_allergic_disorders/allergic_autoimmune_and_other_hypersensitivity_disorders/hereditary_and_acquired_angioedema.html }}</ref>

==Society and culture== thumb|right|250px|Stanozolol 50 mg tablets

===Generic names=== ''Stanozolol'' is the generic name of stanozolol in English, German, French, and Japanese and its {{abbrlink|INN|International Nonproprietary Name}}, {{abbrlink|USAN|United States Adopted Name}}, {{abbrlink|USP|United States Pharmacopeia}}, {{abbrlink|BAN|British Approved Name}}, {{abbrlink|DCF|Dénomination Commune Française}}, and {{abbrlink|JAN|Japanese Accepted Name}}, while ''stanozololum'' is its name in Latin, ''stanozololo'' is its name in Italian and its {{abbrlink|DCIT|Denominazione Comune Italiana}}, and ''estanozolol'' is its name in Spanish.<ref name="IndexNominum2000" /><ref name="Morton_2012">{{cite book | vauthors = Morton IK, Hall JM | title = Concise Dictionary of Pharmacological Agents: Properties and Synonyms | pages = 261– | date = 6 December 2012 | url = https://books.google.com/books?id=tsjrCAAAQBAJ&pg=PA261 | publisher = Springer Science & Business Media | isbn = 978-94-011-4439-1 }}</ref><ref name="Drugs.com" /> ''Androstanazole'', ''androstanazol'', ''stanazol'', ''stanazolol'', and ''estanazolol'' are unofficial synonyms of stanozolol.<ref name="IndexNominum2000" /><ref name="Drugs.com" /> It is also known by its former developmental code name ''WIN-14833''.<ref name="IndexNominum2000" /><ref name="Drugs.com" /><ref name="Morton_2012" />

===Brand names=== Brand names under which stanozolol is or has been marketed include Anaysynth, Menabol, Neurabol Caps., Stanabolic (veterinary), Stanazol (veterinary), Stanol, Stanozolol, Stanztab, Stargate (veterinary), Stromba, Strombaject, Sungate (veterinary), Tevabolin, Winstrol, Winstrol Depot, and Winstrol-V (veterinary).<ref name="IndexNominum2000" /><ref name="Drugs.com" />

===Legal status in the United States=== {{Globalize|section|USA|2name=the United States|date=January 2012}}

In the United States, like other AAS, stanozolol is classified as a controlled substance under federal regulation; they were included as Schedule III controlled substances under the Anabolic Steroids Control Act of 1990 which was passed as part of the Crime Control Act of 1990.<ref>{{cite book | vauthors = Karch SB | title = Pathology, Toxicogenetics, and Criminalistics of Drug Abuse | date = 2007 | publisher = CRC Press | isbn = 978-1-4200-5456-9 }}</ref>{{rp|30}}

===Doping in sports=== {{See also|List of doping in sport cases#Stanozolol}}

Stanozolol and other synthetic steroids were first banned by the International Olympic Committee and the International Association of Athletics Federations in 1974, after methods to detect them had been developed.<ref>{{cite book | vauthors = Shänzer W | veditors = Nieschlag E, Behr HM | chapter = Abuse of Androgens and Detection of Illegal Use Chapter 24 | title = Testosterone: Action, Deficiency, Substitution | date = 2004 | publisher = Cambridge University Press | isbn = 978-1-139-45221-2 }}</ref>{{rp|716}} There are many known cases of doping in sports with stanozolol by professional athletes. Stanozolol is especially widely used by the athletes from post-Soviet countries.{{Citation needed|date=June 2025}} As of 2015, it is banned by World Anti-Doping Agency<ref>{{cite journal | vauthors = Ozcagli E, Kara M, Kotil T, Fragkiadaki P, Tzatzarakis MN, Tsitsimpikou C, Stivaktakis PD, Tsoukalas D, Spandidos DA, Tsatsakis AM, Alpertunga B | title = Stanozolol administration combined with exercise leads to decreased telomerase activity possibly associated with liver aging | journal = International Journal of Molecular Medicine | volume = 42 | issue = 1 | pages = 405–413 | date = July 2018 | pmid = 29717770 | pmc = 5979936 | doi = 10.3892/ijmm.2018.3644 }}</ref> and United States Anti-Doping Agency.<ref>{{Cite web | title = What is Stanozolol? Education, Science, Spirit of Sport / April 29, 2015 | date = 29 April 2015 | url = https://www.usada.org/spirit-of-sport/education/what-is-stanozolol/ | access-date = 2020-09-06 | website = www.usada.org }}</ref>

==Research== Stanozolol has been investigated in the treatment of a number of dermatological conditions including urticaria, hereditary angioedema, Raynaud's phenomenon, cryofibrinogenemia, and lipodermatosclerosis.<ref name="Helfman_1995">{{cite journal | vauthors = Helfman T, Falanga V | title = Stanozolol as a novel therapeutic agent in dermatology | journal = Journal of the American Academy of Dermatology | volume = 33 | issue = 2 Pt 1 | pages = 254–258 | date = August 1995 | pmid = 7622653 | doi = 10.1016/0190-9622(95)90244-9 }}</ref>

== References == {{Reflist}}

Category:Tertiary alcohols Category:Androgens Category:Androstanes Category:CYP17A1 inhibitors Category:Hepatotoxins Category:Pyrazoles Category:Veterinary drugs Category:Muscle protectors Category:Heterocyclic compounds with 5 rings