S-23

S-23 is an investigational selective androgen receptor modulator (SARM) developed by the company GTX, Inc. It has not been approved for clinical use and is currently classified as an investigational new drug in the U.S. It is a type of chemical that mimics the activity of testosterone in the body. 

Different Names

• (S)-N-(4-cyano-3-trifluoromethyl-phenyl)-3-(3-fluoro-4-chlorophenoxy)-2-hydroxy-2-methyl-propanamide

• GTX-023

• CCTH-methylpropionamide

• (+)-S-23

Side Effects and Risks

Because S-23 is an unapproved, investigational drug, the full scope of its side effects and risks in humans is not well-documented. However, based on preliminary research and general concerns about SARMs, the following are potential side effects:

• Liver injury and acute liver failure: The FDA warns that SARMs, including S-23, may be associated with liver damage.

• Cardiovascular risks: There is an increased risk of heart attack or stroke.

• Hormonal suppression: S-23, like other SARMs, can suppress the body's natural production of hormones, particularly testosterone. This can lead to infertility, testicular atrophy (shrinkage), and other forms of sexual dysfunction.

• Psychological effects: Some research has linked hormonal compounds to adverse mental health outcomes, including depression, psychosis, and hallucinations.

• Other side effects: Sleep disturbances and miscarriage have also been cited as potential risks.

Benefits and Pros

S-23 has been investigated in animal models for its potential therapeutic benefits, which are often cited by those who use it for performance enhancement.

• Anabolic Effects: In animal studies, S-23 has shown a dose-dependent increase in lean body mass (LBM) and bone mineral density (BMD) while reducing fat mass.

• Male Contraception: S-23 was primarily developed as a potential hormonal male contraceptive. In animal studies, it showed a dose-dependent suppression of spermatogenesis (sperm production) that was reversible upon cessation of treatment.

• Muscle Preservation: Due to its anabolic properties, it's been explored as a way to preserve muscle and bone mass in conditions like orchiectomy (removal of testes).

Cons

• Lack of FDA Approval: The most significant con is that S-23 is not approved for human use and is considered an investigational drug. Its long-term effects on humans are unknown.

• Serious Health Risks: As noted above, it is associated with severe potential side effects, including liver damage, heart attack, and stroke.

• Hormonal Suppression: Its strong suppressive effects on natural testosterone production necessitate a post-cycle therapy (PCT) to restore hormonal balance, adding to the complexity and risk of its use.

• Legality and Regulation: It is banned by major anti-doping agencies, and the FDA has taken legal action against companies selling products containing SARMs.

Dosage and Frequency

There is no reliable information on a safe or appropriate dosage for humans. Animal studies used doses in the range of 0.01-3 mg/day, but this cannot be directly translated to human use. The lack of clinical trials on humans means there are no standardized dosing protocols.

Half-Life and Detection Time

• Half-Life: In male rats, the half-life of S-23 was found to be approximately 11.9 hours after oral administration. This means it takes about 12 hours for half of the drug to be eliminated from the body.

• Detection Time: Due to its status as a research chemical, there is limited data on its specific detection time in humans. However, as it is a banned substance by WADA, it is included in drug tests for athletes. SARMs, in general, can be detectable for several weeks or even months after a last dose, depending on the dosage, duration of use, and individual metabolism.

Sterogenic, Progestronic, and Prolactin Effects

• Sterogenic: S-23 is an arylpropionamide selective androgen receptor modulator, not a steroidal compound. It binds to the androgen receptor (AR) as a full agonist, meaning it activates the receptor to its maximum potential.

• Progestronic and Prolactin Effects: The provided search results do not contain information on S-23's progestronic or prolactin effects. However, due to its strong androgenic activity and suppression of natural hormones, it is possible it could indirectly influence other hormonal pathways. It is not known to be a progestin or have direct prolactin-like effects.

Anabolic Androgenic Ratio

Preclinical animal studies have shown that S-23 has a good ratio of anabolic to androgenic effects. In castrated male rats, the ED50 (the dose that produces a therapeutic effect in 50% of the animals) for anabolic activity (levator ani muscle) was 0.079 mg/d, while the ED50 for androgenic activity (prostate) was 0.43 mg/d. This suggests a ratio that favors anabolic effects, but a specific, numbered ratio like those sometimes associated with steroids (e.g., 10:1) is not readily available from the provided search results.