S-23 — Safety, Research, Risks & Legal Status

Not medical advice. S-23 is discussed here for informational and harm-reduction purposes only. We do not endorse use, and any dosing context is informational, not a protocol.

Also known as	S23
Category	SARM
molecular_weight	389.5 g/mol (reported)
purity_risk	Research-chemical form typically 85-98 percent; contamination common
US legal status	Not FDA-approved for human use. Sold exclusively as a research chemical. WADA-banned substance. No legitimate pharmaceutical source.

What is S-23?

Nonsteroidal selective androgen receptor modulator (SARM). Synthetic compound designed to selectively bind androgen receptors in muscle and bone. Third-generation SARM in development phase.

How it works

Binds androgen receptor alpha and beta with high selectivity, activating anabolic pathways in muscle and bone tissue. Unknown tissue-specific distribution and receptor subtype selectivity in humans.

Background & history

Developed as third-generation SARM by academic research institutions. Never advanced to human clinical trials; preclinical phase terminated due to resource constraints.

What the research says

Limited human data; most evidence from animal studies. Preclinical research suggests dose-dependent effects on muscle and bone. No published Phase II/III human trials. Animal studies report anabolic effects on muscle mass and bone density, with testicular atrophy at higher doses. Suppression of endogenous testosterone expected.

Reported effects

Reported anabolic activity in muscle tissue
Studied for potential bone density effects
Preclinical research suggests androgen receptor selectivity
May suppress endogenous testosterone production
Liver and prostate signals observed in animal models

Dosing & administration (informational)

Animal studies used variable dose ranges to assess efficacy and toxicity. Human equivalent dosing unknown; no established reference range for experimental self-use.

This is general research/context information, not medical advice or a recommended protocol.

Safety & side effects

No human safety data; significant unknown risks
Suppression of natural testosterone production expected
Animal studies indicate potential liver and cardiovascular toxicity signals
WADA-banned; prohibited in competitive sport
Unregulated source quality and purity risk extremely high
Off-label self-use is experimentally unvalidated and dangerous

Drug & supplement interactions

Potential additive suppression with other androgens or SARMs
Unknown interaction with sex hormone-binding globulin (SHBG)
Hepatic metabolism may compete with drug metabolism pathways
Possible antagonism with estrogen receptor modulation

Who should avoid it

Concurrent use with anabolic steroids or other SARMs
In individuals with hepatic or cardiovascular disease history
In those with hypogonadism or testosterone recovery needs
During competitive sport or drug-tested athletics

How it is commonly combined

No validated human data on combinations; co-use with other research compounds dramatically increases unknown risk.

Legal & regulatory. Not FDA-approved for human use. Sold exclusively as a research chemical. WADA-banned substance. No legitimate pharmaceutical source.

Quality & harm reduction

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Lab testing & harm-reduction tools

If you are going to research a compound, verifying identity and purity is the single most protective step. Independent analytical testing and sterile-handling supplies reduce risk.

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Frequently asked questions

Is S-23 legal?

No. Not approved for human use anywhere. Sold as 'research chemical' but human sale/use is legally risky and unvalidated.

Why is it WADA-banned?

Its androgenic effects and suppressive profile trigger anti-doping rules.

What research exists on humans?

Essentially none. Preclinical only. Human use is experimental.

Why is product quality so uncertain?

No pharmaceutical regulation, no manufacturing standards, no buyer recourse if contaminated or mislabeled.

What is the main risk?

Testosterone suppression, organ damage signals in animals, completely unproven in people.

References & further reading

WADA Prohibited List (SARMs class)
FDA guidance on investigational SARM development
PubMed preclinical studies on S-23 androgen receptor binding