S23
The High-Affinity SARM for Contraceptive Research
01
Overview
S23 is a non-steroidal selective androgen receptor modulator developed by GTX Inc. with exceptionally high binding affinity for the androgen receptor. It is notable for being one of the most potent SARMs studied and for its investigation as a potential male hormonal contraceptive due to its ability to suppress spermatogenesis while maintaining libido and muscle mass.
02
Mechanism of Action
S23 binds the androgen receptor with very high affinity, producing full agonist activity in muscle and bone. Its contraceptive effect arises from suppression of gonadotropins (LH/FSH) through negative feedback at the hypothalamic-pituitary axis, reducing intratesticular testosterone and halting spermatogenesis while peripheral androgen signaling is maintained by S23 itself.
03
Research Highlights
Contraceptive research in rats shows 99% effective spermatogenesis suppression that is reversible after discontinuation
Muscle and bone studies demonstrate potent anabolic activity exceeding earlier SARMs
Libido research confirms maintained sexual behavior despite suppressed endogenous testosterone
04
Dosage
Administration & Timing
Oral administration (capsule or solution), once daily. Research protocols administer independent of food.
Dosage Guidelines
Cycle Length
6–8 weeks; followed by PCT — S23 is notably suppressive.
05
Reconstitution
Solvent
Not applicable — orally dosed capsule or solution
Volume
N/A
Concentration
10–30 mg per unit dose
Storage
Store at room temperature (15–25 °C); protect from moisture.
Notes
S23 is among the most suppressive SARMs in research. Investigational as a male hormonal contraceptive; handle conservatively.
Research Reference Only
Dosage and reconstitution values reflect commonly cited ranges from published research literature and are presented for educational and research reference only. This is not medical advice or a dosing recommendation. HEXAGEN does not endorse human use of any compound. Always consult a qualified healthcare professional.
Research Disclaimer
S23 is for educational and research purposes only. Not intended as medical advice. Consult a qualified healthcare professional before making any health-related decisions.
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S23 — Common Research Questions
What is S23?
S23 is a non-steroidal selective androgen receptor modulator developed by GTX Inc. with exceptionally high binding affinity for the androgen receptor. It is notable for being one of the most potent SA... S23 belongs to the Non-Peptide Research research category and is studied for its the high-affinity sarm for contraceptive research.
How does S23 work?
S23 binds the androgen receptor with very high affinity, producing full agonist activity in muscle and bone. Its contraceptive effect arises from suppression of gonadotropins (LH/FSH) through negative feedback at the hypothalamic-pituitary axis, reducing intratesticular testosterone and halting spermatogenesis while peripheral androgen signaling is maintained by S23 itself.
What are the key research benefits of S23?
Among the highest AR binding affinities of any SARM. Potent anabolic effects on skeletal muscle. Male contraceptive research — reversible spermatogenesis suppression. Bone density and strength improvement. Maintained libido via central androgen signaling. High tissue selectivity for muscle and bone.
What is the molecular structure of S23?
S23 is a research compound in the Non-Peptide Research category. Detailed molecular structure data is being compiled. Refer to primary literature for structural analysis.
What does the research say about S23?
Contraceptive research in rats shows 99% effective spermatogenesis suppression that is reversible after discontinuation Muscle and bone studies demonstrate potent anabolic activity exceeding earlier SARMs Libido research confirms maintained sexual behavior despite suppressed endogenous testosterone These findings are based on preclinical and clinical research. S23 is a research compound and these studies do not constitute medical advice.
Is S23 FDA approved?
No. S23 is not FDA-approved for any indication. It is a research chemical studied in preclinical and early clinical research. These compounds are not approved for human therapeutic use and should only be studied in appropriate research settings.
What category does S23 belong to?
S23 belongs to the Non-Peptide Research category, which focuses on selective androgen receptor modulators and other novel research compounds studied for their unique pharmacological profiles. You can explore more compounds in this category on the Non-Peptide Research pillar page.
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Scientific References
Contraceptive research in rats shows 99% effective spermatogenesis suppression that is reversible after discontinuation
Muscle and bone studies demonstrate potent anabolic activity exceeding earlier SARMs
Libido research confirms maintained sexual behavior despite suppressed endogenous testosterone