YK-11
YK11
Half-life
8 hr
Time to Peak
1.5 hr
Steady State
~2 days
Dose Range
5–20 mg
Frequency
Twice daily
Overview
Synthetic steroidal compound with dual SARM / myostatin-inhibitor properties. Structurally derived from 5-alpha-dihydrotestosterone (DHT) — unusual among SARMs. Community interest driven by claims of myostatin inhibition which theoretically removes the upper limit on muscle growth. Harm reduction: Potentially more androgenic than typical SARMs due to steroidal structure. Liver enzyme elevation reported — TUDCA recommended. HPG suppression observed. Human data is entirely anecdotal. Half-life estimated 6–10 hours from structural analogy — multiple daily doses. Injectable form used by some for higher bioavailability.
Mechanism of Action
Partial agonist at the androgen receptor. In vitro: induces follistatin expression, which binds and inhibits myostatin (GDF-8/11), theoretically removing the endogenous ceiling on muscle hypertrophy. Steroidal structure raises concern about full androgenic activity at high doses.
Dosing Information
| Route | Dose Range | Half-life | Tmax | Frequency |
|---|---|---|---|---|
| Oral | 5–20 mg | 8 hr | 1.5 hr | Twice daily, three times daily |
| Intramuscular (IM) | 2–10 mg | 12 hr | 2 hr | Every other day, three times weekly |
Storage & Handling
Room temperature — Store below 25C. Protect from light. Injectable: oil-based solution. Oral: capsule or liquid suspension.
Used in Regimens
YK-11 is not currently part of any catalog regimen.
Data Sources
- Community r/steroids Compound Experience Directory
Related Tools
Track YK-11 with Doseline
Reminders, medication level charts, injection site rotation, and protocol tracking — all free, all private.
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