Checked 2026-11-10. Independent clinical review has not been completed. WADAFUK is independent of WADA and does not provide medical advice or an individual anti-doping determination.
Prohibited at all times
YK-11 is covered by S1.2 of the effective 2026 WADA List and is prohibited in and out of competition. The S1.2 examples do not exhaust the category. [5]
S1.2; 2026 List, printed pages 5–6 · 2026 rules apply from 1 January 2026. Any 2027 material below concerns future rules from 1 January 2027; it is not current clearance.
Approval and safety context
FDA states that SARMs are unapproved and warns of serious health problems. This class warning does not quantify this compound’s individual risk. [3]
- Research use and commercial availability are not evidence of safety or authorization.
Cell research and exposure
YK11 research in C2C12 mouse muscle precursor cells found androgen-receptor-related differentiation and increased follistatin expression. Separately, a metabolism paper describes YK11 identified in a seized product and a urinary elimination study. [1] [2]
- Cell findings do not show that YK11 builds muscle or safely inhibits myostatin in people. A metabolism study is not an efficacy or safety trial.
List year
The 2026 List is the effective edition on this review date. The checked 2027 S1 text showed no change, but the 2027 edition does not take effect until 1 January 2027. [5] [6] [4]
- Consult the official edition and responsible anti-doping organization for consequential decisions. This reference does not provide medical advice, a TUE decision, product certification or individual clearance.
What remains uncertain
- This is a targeted source check, not a systematic review or independent clinical/regulatory sign-off. Uncited draft claims remain unpublished.
- Chemical registry identifiers, every alias and jurisdiction-specific product availability have not been exhaustively reconciled.
Check the sources.
These are concise editorial paraphrases of selected sources, not a systematic review or a reproduction of source tables. Access depth is shown for each reference; an abstract-only check cannot resolve details found only in a full paper.
- Selective androgen receptor modulator, YK11, regulates myogenic differentiation of C2C12 myoblasts by follistatin expression. ↗Accessed 2026-11-10 · indexed original abstract read via Europe PMC MED record; full article not reviewed
Abstract; PMID 23995658
- Studies on the in vivo metabolism of the SARM YK11: Identification and characterization of metabolites potentially useful for doping controls. ↗Accessed 2026-11-10 · indexed original abstract read via Europe PMC MED record; full article not reviewed
Abstract; PMID 30379415
- FDA Warns of Use of Selective Androgen Receptor Modulators (SARMs) Among Teens, Young Adults ↗Accessed 2026-11-10 · relevant primary-source text read
Consumer warning, approval status and reported serious risks
- 2027 Prohibited List resource page ↗Accessed 2026-11-10 · relevant primary-source text read · FUTURE 2027 SOURCE
Resource description and effective date
- WADA 2026 Prohibited List ↗Accessed 2026-11-10 · relevant primary-source text read
Introduction and S1, printed pages 3, 5–6
- WADA 2027 Prohibited List, currently linked English file ↗Accessed 2026-11-10 · relevant primary-source text read · FUTURE 2027 SOURCE
Cover and S1, printed pages 1, 5–6
Check the current official WADA List and the relevant anti-doping authority for your sport, product, route and circumstances. Do not stop or change necessary treatment based on this page. Ask a qualified clinician about health decisions. Missing evidence does not establish safety.