S-4 Andarine (25mg x 60 Capsules) s4

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S-4 is in a class of androgen receptor ligands that is tissue selective, developed to treat muscle wasting associated with cancer, acute and chronic illness and age-related muscle loss.


S-4 was studied in 120 ovariectomized rats (a female rat whose ovaries have been removed) for 120 days. The study found that treatment with S4 (S-4) was beneficial to maintain cortical bone content and whole-body bone mineral density (BMD) measured by DEXA scan. The S4 treatment also decreased body fat and increased body strength in these animals. It was also revealed that S-4 provides the unique potential to prevent bone resorption, increase skeletal muscle mass and promote bone anabolism, making it a possible new alternative treatment for osteoporosis and sarcopenia 4. To date there are no clinical human studies with S-4. S-4 has a half-life of 4-6 hours and is prized as a weight loss and muscle boosting supplement in the fitness community.

Dosages of 25 – 100 mg per day are commonly used in a recreational context for muscle building purposes. There is no established therapeutic dosage of S4.

Typically, users report more favorable outcomes splitting their daily dosage up into increments throughout the day to maintain stable blood serum concentration levels to account for S-4’s short 4 hour half-life. Anecdotally, S4 is reported to exhibit diminishing returns at dosages above 100 mg per day, with 50 mg commonly being referred to as “the sweet spot” dosage.

Vision side effects are reported to occur in a significant number of users at dosages above 50 mg per day.

These dosages were determined by recreational users based upon personal experimentation and anecdotal experiences and are not indicative of correct or incorrect use.

Side Effects from S-4

Users may experience a suppression in luteinizing hormone (LH) and follicle stimulating hormones (FSH) from S-4 usage. LH and FSH promote the production of reproductive hormones in men and women, and suppression could suppress normal estrogen/testosterone levels. However, it is unknown if and how much S-4 would actually suppress testosterone/estrogen production in humans. S-4 suppressed LH and FSH in castrated rats but had no effect in normal male rats.

Besides suppression, the most frequent user-reported side effect is visual issues such as seeing a yellow tint and difficulty adjusting to night vision. The S-4 molecule binds to the retina in the eye which causes a yellow tint to be seen. This generally occurs at night, especially when switching from a dark to lightened area. The side effect is not serious and will disappear immediately after the drug’s usage has been discontinued.

“More men’s physique competitors have won competitions using only S4 then any other compound. It appears to be an adequate replacement for steroids in amateur physique divisions.

I personally don’t like it because even though the vision side effects are mild and temporary, I can’t afford any vision compromise because I’m constantly on my phone. It appears that the vision side effects and benefits are directly related to dosage and duration of cycle. Men seem to get great benefits from longer cycles at 50mg/day, or short cycles at 75-100mg/day. We also have had a lot of female competitors who have won physique competitions using only 25-50mg/day. Which is surprisingly close to a man’s dosage, but they experienced no virilization side effects.

S4 gives a dry hard look to the muscles and maintains performance while dieting.

I defiantly recommend cycling off because of the vision side effect. I personally like running a higher dosage for a short period of time before side effects accumulate.”

  • Dr Tony Huge


“I experienced vision side effect from oral S4. Even low dosages caused the vision side effects. I’m not a fan of oral S4, especially at high dosages.

I have gone up to 150mg/day with injectable S4 with no vision side effects. It really dried out and hardened my physiques. My veins came out like crazy. Similar results to Winstrol. I recommended dosages of 50-100mg/day for men. At low dosages, it’s great for women. I recommend dosages of 10-25md/day for women. Women start to get side effects at dosages about 50mg/day.

S4 has a short half-life so it’s something you would to add into a stack instead of using is as the primary drug of choice.”

  • Coach Trevor
Weight 3 kg
Dimensions 2.0 × 1.0 × 1.0 cm

60 capsules of 25mg each

Other Ingredients

USP Microcrystalline cellulose, magnesium stearate, gelatin


NOT APPROVED FOR SALE IN THE UNITED STATES. The end user and/or importer is responsible for all domestic laws. Enhanced Athlete and/or its affiliates assumes no responsibility for the misuse of this product.

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