S-23

A profile on S-23, widely considered the strongest and most suppressive SARM, originally developed as a male contraceptive.

S-23

S-23 is often cited as the strongest SARM currently available. Developed by GTX, Inc, it was investigated as a potential male hormonal contraceptive.

In the bodybuilding world, it is the SARM equivalent of Winstrol or Masteron on steroids. It creates an incredibly hard, dry, grainy look. However, it comes with a guarantee: it will shut down your natural testosterone production completely.

Quick Specs

PropertyValue
Active CompoundS-23
Half-Life~12 Hours
Detection TimeUnknown
Anabolic/Androgenic RatioVery High : High
Chemical FamilySARM
AdministrationOral

Mechanism of Action

S-23 has a higher binding affinity for the androgen receptor than any other SARM (and stronger than Testosterone).

Contraceptive Action: In studies, S-23 suppressed LH and FSH (the hormones that signal the testes to work) to zero. It induces temporary infertility. Because of this, running S-23 without a Testosterone Base (TRT) leads to zero estrogen and zero testosterone, causing miserable side effects.

Pharmacokinetics & Dosing

Half-Life: ~12 Hours

  • Frequency: Twice Daily (AM/PM) is mandatory.
  • Dosage: 10mg to 30mg per day.
  • Test Base: Mandatory. You cannot run S-23 solo. You must use injectable Testosterone or a 4-Andro base to maintain physiological functions.

Primary Effects

1. Extreme Hardness

S-23 sucks water out of the body and hardens muscles significantly. It is a premier pre-contest polisher.

2. Catabolism Prevention

It creates a powerful nitrogen-retaining environment, allowing for muscle gain even in steep caloric deficits.

3. Strength

Strength gains are rapid and aggressive.

Side Effects & Harm Reduction

Aggression:

Roid Rage: S-23 is one of the few SARMs known to cause genuine aggression and irritability ("roid rage"). It has a distinct impact on the CNS.

1. Total Shutdown

This is not "suppression." It is shutdown. Your balls will atrophy. A full, aggressive PCT (Post Cycle Therapy) with HCG and SERMs is required if you are not on TRT.

2. Night Sweats & Cramps

Severe night sweats and muscle cramps are very common. Electrolyte/Taurine supplementation is required.

3. Hair Loss

It is notoriously harsh on the hairline.

Tracking S-23

Using the Anabolic Tracker app:

  1. Inventory: Add S-23.
  2. Scheduling: Twice Daily.
  3. Metrics: Track Aggression (1-10) and Sleep Quality.
  4. Notes: Ensure you are logging your Testosterone Base alongside this. If you miss your Test shots while on S-23, you will feel crash symptoms immediately.

Disclaimer:

This guide is for informational purposes only. S-23 is an unapproved research chemical.

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