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OSTARINE

Other Names:

Enobosarm, GTx-024, MK-2866, S-22

Review this Treatment 14 User Reviews See Brand Products

OSTARINE Overview Information

Ostarine is a type of drug called a selective androgen receptor modulator (SARM). It's not approved by the FDA, but is sometimes found in supplements.

Ostarine attaches to proteins in the body known as androgen receptors. When ostarine binds to these receptors, it tells muscles to grow.

People use ostarine for athletic performance, involuntary weight loss due to illness, breast cancer, and many other conditions, but there is no good scientific evidence to support these uses.

Ostarine is an investigational drug and therefore not approved for any use by the US FDA. Despite this, it is still sometimes found in dietary supplements, particularly those marketed for bodybuilding. Ostarine, along with other SARMS, is banned by the World Anti-Doping Agency (WADA) and the National Collegiate Athletic Association (NCAA).

OSTARINE Uses & Effectiveness

We currently have no information for OSTARINE Uses & Effectiveness

OSTARINE Side Effects & Safety

When taken by mouth: Ostarine is possibly unsafe. It might cause liver damage and other serious side effects such as heart attack.

Special Precautions & Warnings:

Pregnancy and breast-feeding: There isn't enough reliable information to know if ostarine is safe to use when pregnant or breast-feeding. Stay on the safe side and avoid use.

Liver problems: Ostarine might cause liver problems in some people. People with a history of liver problems should avoid ostarine.

OSTARINE Interactions

We currently have no information for OSTARINE Interactions

OSTARINE Dosing

Ostarine has most often been used by adults in doses of 3 mg by mouth daily for 12-16 weeks. Speak with a healthcare provider to find out what dose might be best for a specific condition.

Keep in mind that ostarine is an unapproved drug. It is also banned by WADA and the NCAA.

View clinical references for this vitamin or supplement Sources

References:

2017-18 NCAA Banned Drugs List. National Collegiate Athletic Association (NCAA), June 5, 2017. https://www.ncaa.org/2017-18-ncaa-banned-drugs-list. Accessed: Sept 7, 2017

Bedi H, Hammond C, Sanders D, Yang HM, Yoshida EM. Drug-induced liver injury from enobosarm (ostarine), a selective androgen receptor modulator. ACG Case Rep J 2021;8(1):e00518. View abstract.

Coss CC, Jones A, Dalton JT. Pharmacokinetic drug interactions of the selective androgen receptor modulator GTx-024 (enobosarm) with itraconazole, rifampin, probenecid, celecoxib and rosuvastatin. Invest New Drugs 2016;34(4):458-67. View abstract.

Dalton JT, Barnette KG, Bohl CE, et al. The selective androgen receptor modulator GTx-024 (enobosarm) improves lean body mass and physical function in healthy elderly men and postmenopausal women: results of a double-blind, placebo-controlled phase II trial. J Cachexia Sarcopenia Muscle 2011;2(3):153-61. View abstract.

Dart DA, Kandil S, Tommasini-Ghelfi S, et al. Novel trifluoromethylated enobosarm analogues with potent antiandrogenic activity in vitro and tissue selectivity in vivo. Mol Cancer Ther 2018;17(9):1846-58. View abstract.

Dobs AS, Boccia RV, Croot CC, et al. Effects of enobosarm on muscle wasting and physical function in patients with cancer: a double-blind, randomised controlled phase 2 trial. Lancet Oncol 2013;14(4):335-45. View abstract.

Dubois V, Simitsidellis I, Laurent MR, et al. Enobosarm (GTx-024) modulates adult skeletal muscle mass independently of the androgen receptor in the satellite cell lineage. Endocrinology 2015;156(12):4522-33. View abstract.

Dynamic Technical Formulations, LLC. Issues a Voluntary Nationwide Recall of Tri-Ton Due to the Presence of Andarine and Ostarine. FDA Recalls, Market Withdrawals, & Safety Alerts, May 19, 2017. https://www.fda.gov/Safety/Recalls/ucm559700.htm?source=govdelivery&utm_medium=email&utm_source=govdelivery. Accessed: Sept 7, 2017.

FDA. FDA Warns against using SARMs in body building products. October 2017. Available at: https://www.fda.gov/newsevents/newsroom/fdainbrief/ucm583021.htm.

Gheddar L, Raul JS, Kintz P. Development and validation of SARMs and metabolic modulators screening in hair using UHPLC-MS/MS: Application to a doping case and first identification of S23 in authentic human hair. J Chromatogr B Analyt Technol Biomed Life Sci 2021;1187:123048. View abstract.

Kintz P, Gheddar L, Paradis C, et al. Peroxisome Proliferator-Activated Receptor Delta Agonist (PPAR- d) and Selective Androgen Receptor Modulator (SARM) Abuse: Clinical, Analytical and Biological Data in a Case Involving a Poisonous Combination of GW1516 (Cardarine) and MK2866 (Ostarine). Toxics 2021;9(10):251. View abstract.

Komrakova M, Büchler G, Böker KO, et al. A combined treatment with selective androgen and estrogen receptor modulators prevents bone loss in orchiectomized rats. J Endocrinol Invest 2022;45(12):2299-2311. View abstract.

Komrakova M, Furtwängler J, Hoffmann DB, Lehmann W, Schilling AF, Sehmisch S. The selective androgen receptor modulator ostarine improves bone healing in ovariectomized rats. Calcif Tissue Int 2020;106(2):147-157. View abstract.

Komrakova M, Nagel J, Hoffmann DB, Lehmann W, Schilling AF, Sehmisch S. Effect of selective androgen receptor modulator enobosarm on bone healing in a rat model for aged male osteoporosis. Calcif Tissue Int 2020;107(6):593-602. View abstract.

Leciejewska N, Kolodziejski PA, Sassek M, Nogowski L, Malek E, Pruszynska-Oszmalek E. Ostarine-Induced Myogenic Differentiation in C2C12, L6, and Rat Muscles. Int J Mol Sci 2022;23(8):4404. View abstract.

Leciejewska N, Pruszynska-Oszmalek E, Bien J, Nogowski L, Kolodziejski PA. Effect of ostarine (enobosarm/GTX024), a selective androgen receptor modulator, on adipocyte metabolism in Wistar rats. J Physiol Pharmacol 2019;70(4). View abstract.

Roch PJ, Henkies D, Carstens JC, et al. Ostarine and ligandrol improve muscle tissue in an ovariectomized rat model. Front Endocrinol (Lausanne) 2020;11:556581. View abstract.

Roch PJ, Wolgast V, Gebhardt MM, et al. Combination of selective androgen and estrogen receptor modulators in orchiectomized rats. J Endocrinol Invest 2022;45(8):1555-1568. View abstract.

Selective Androgen Receptor Modulators (SARMs) - A Prohibited Class of Anabolic Agents. U.S. Anti-Doping Agency, November 18, 2015. https://www.usada.org/selective-androgen-receptor-modulators-sarms-prohibited-class-anabolic-agencts/. Accessed: August 30, 2017.

Thevis M, Geyer H, Thomas A, Schänzer W. Trafficking of drug candidates relevant for sports drug testing: detection of non-approved therapeutics categorized as anabolic and gene doping agents in products distributed via the Internet. Drug Test Anal 2011;3(5):331-6. View abstract.

USADA. Athlete Advisory: Ostarine in Supplements. July 2017. Available at: https://www.usada.org/growing-evidence-ostarine-athlete-risk/.

Van Wagoner RM, Eichner A, Bhasin S, Deuster PA, Eichner D. Chemical composition and labeling of substances marketed as selective androgen receptor modulators and sold via the internet. JAMA 2017;318(20):2004-10. View abstract.

WADA. What is prohibited. 2019 list of prohibited substances and methods. Available at: https://www.wada-ama.org/en/content/what-is-prohibited/.

Warning Letter: Infantry Labs LLC 10/23/17. FDA Inspections, Compliance, Enforcement, and Criminal Investigations, October 23, 2017. https://www.fda.gov/iceci/enforcementactions/warningletters/2017/ucm582685.htm. Accessed: November 1, 2017

Warning Letter: Ironmag Labs 10/23/17. FDA Inspections, Compliance, Enforcement, and Criminal Investigations, October 23, 2017. https://www.fda.gov/iceci/enforcementactions/warningletters/2017/ucm582464.htm Accessed: November 1, 2017

Warning Letter: Panther Sports Nutrition 10/23/17. FDA Inspections, Compliance, Enforcement, and Criminal Investigations, October 23, 2017. https://www.fda.gov/iceci/enforcementactions/warningletters/2017/ucm581630.htm. Accessed: November 1, 2017

Weinblatt D, Roy S. Drug-Induced Liver Injury Secondary to Enobosarm: A Selective Androgen Receptor Modulator. J Med Cases 2022;13(5):244-248. View abstract.

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Conditions of Use and Important Information: This information is meant to supplement, not replace advice from your doctor or healthcare provider and is not meant to cover all possible uses, precautions, interactions or adverse effects. This information may not fit your specific health circumstances. Never delay or disregard seeking professional medical advice from your doctor or other qualified health care provider because of something you have read on WebMD. You should always speak with your doctor or health care professional before you start, stop, or change any prescribed part of your health care plan or treatment and to determine what course of therapy is right for you.

This copyrighted material is provided by Natural Medicines Comprehensive Database Consumer Version. Information from this source is evidence-based and objective, and without commercial influence. For professional medical information on natural medicines, see Natural Medicines Comprehensive Database Professional Version. © Therapeutic Research Faculty 2009.

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