YK-11 Reference

Plain English

What it is

YK-11 is a SARM, a lab-made drug that targets muscle-building hormone signals. It is sold only as a research chemical and is not an approved medicine. Its structure is steroidal, which makes it act more like an anabolic steroid than most other SARMs.

What people use it for

In bodybuilding and body-recomposition circles, people talk about using it to build muscle and look leaner. It is often marketed as a 'myostatin inhibitor,' meaning a way to release the body's natural brake on muscle growth. These uses come from personal stories and are not an approved medical use.

What the science shows

The published research on YK-11 is early-stage and done in cell cultures, mainly showing that it switches on a protein called follistatin that pushes muscle cells to grow. There have been no human trials, so its real effects and safety in people are still unknown.

The catch

SARMs like YK-11 are not approved by the FDA for human use, and the FDA acts against companies that sell them. The World Anti-Doping Agency bans all SARMs in sport at all times as anabolic agents (class S1.2). Because YK-11 behaves much like an anabolic steroid, reported risks include liver strain and lower natural testosterone, and steroid-like compounds can also worsen cholesterol and heart health.

Reference summary

Published work is preclinical, focused on myogenic-cell follistatin induction and muscle-protein synthesis in cell culture. No human trials.

Regulatory and posture

Categories

SARM, Recovery

Aliases

Steroidal SARM, Myostatin-inhibitor-class compound

Evidence posture

preclinical - FDA enforcement attention. Sold only as a research chemical, not for human consumption per legal seller terms. WADA-prohibited under category S1.2 at all times. Steroidal skeleton - closer to anabolic-androgen pharmacology than non-steroidal SARMs; hepatotoxicity and HPTA suppression are reported in user accounts. No FDA-approved drug label.

Regulatory status

No FDA-approved YK-11 drug label. WADA prohibits SARMs under category S1.2 at all times. FDA enforcement against SARMs sellers applies. YK-11 is a steroidal scaffold compound - pharmacologically closer to anabolic-androgen pharmacology than non-steroidal SARMs.

Content review status

research reference

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