A Brief Look at Mastorine (S23)
Mastorine, also known as S23, is considered one of the most potent SARMs available for building lean muscle mass and increasing strength. It gives an extremely firm and dry physique, and users value it during the advanced stages of physical recovery.
Compared to other SARMs, Mastorine (S23) presents the highest level of testosterone suppression, a feature that makes it suitable only for experienced and knowledgeable users.

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What is Mastorine (S23)?

S23 is a next-generation SARM developed from the structure of an older compound called C-6. The main chemical modification involves replacing the para-nitro group at the C-6 position with a cyano group.
This change led to a marked improvement in pharmacokinetics because while C-6 had an oral bioavailability of approximately 76 percent, Mastorine (S23) reaches up to 96% oral bioavailability, making it efficient at low dosages.

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Research data

Mastorine (S23) is currently in the process of preclinical development and researchers have studied it exclusively in animal models.
Tests showed that S23 is the most potent SARM ever tested, causing complete infertility in the treated rats. For this reason, science views it as a potential male hormonal contraceptive.
To date, researchers have conducted no clinical studies in humans.

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User perspectives

In the world of bodybuilding, Mastorine (S23) gains popularity for its extremely powerful effects on muscle mass and definition.
Many users consider it a more potent version of Andarine (S4), without the visual side effects typical of the latter compound.
Some reports suggest a possible reduction in prostate size, but this effect is dose-dependent and often misunderstood.

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Main effects

• High effectiveness in building lean muscle mass
• Sharp increase in strength and performance

• Physical Appearance dry, dense, and highly defined

• Training intensity

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Side effects

• Marked suppression of endogenous testosterone
• Reports of insomnia and nervousness, similar to those observed with trenbolone

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Liver impact

There are currently no specific studies on the Hepatotoxicity of Mastorine (S23).
Although it is a very potent SARM, from a chemical standpoint it should prove to be less taxing on the liver than YK-11 because it features fewer methylated groups.

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Testosterone suppression

Mastorine (S23) It is universally considered the SARM that suppresses testosterone the most currently available.
Its use therefore requires very careful planning and appropriate support strategies.

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Profile

• Half-life: about 12 hours

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Dosage

• Beginners take 10 mg per day

• Average dosage is 15–30 mg per day
• Recommended maximum is 50 mg per day

• Women take 5–10 mg per day