S23 Mastorin S-23

S-23 is a selective androgen receptor modulator (SARM) from Syncom Labs, supplied here in liquid form at 25mg/30ml. It binds strongly to androgen receptors in muscle and bone tissue, which is why users report fast lean mass gains, added strength and a dry, hard look. It is one of the more potent SARMs on the market, and that strength comes with a heavier side effect profile than milder compounds like ostarine.

As a guide only, and not medical advice, experienced users commonly run 10mg per day for the first two weeks, then step up to 15mg per day through week six, staying under 20mg per day. Cycles are usually kept to 6 to 8 weeks. This is not a beginner SARM, so first-timers are generally steered toward something milder such as ostarine or LGD-4033.

Yes, S-23 causes significant testosterone suppression and a PCT is considered necessary. A common approach is nolvadex at 40mg daily for two weeks, tapering to 20mg daily for another two weeks, or clomid at 50mg daily for four weeks, started a couple of days after the last dose. Bloodwork before, mid-cycle and after PCT is the sensible way to track how your hormones are recovering.

Reported effects include marked drops in natural testosterone, reduced HDL cholesterol, raised liver enzymes, and androgenic sides such as hair loss or acne in sensitive users. Many people run a testosterone base alongside S-23 to offset the suppression, plus a liver support product such as N2Guard given the strain on liver enzymes. A full lipid and liver panel before and after a cycle is worth doing given these risks.

S-23 sits well above ostarine and LGD-4033 in terms of both strength and suppression. Where ostarine is often used by first-time SARM users with minimal hormonal impact, S-23 is closer in effect to a mild oral steroid and needs a proper testosterone support plan and PCT. Cardarine is a common addition to an S-23 cycle since it helps offset the cholesterol impact and adds an endurance benefit.

Every bottle sold here is authentic Syncom Labs product with a verification check-code printed on the box so you can confirm it against the manufacturer. Orders placed before midday on a working day usually go out the same day via Royal Mail Tracked 24, arriving within 1 to 2 working days for most UK addresses. Everything is sent in plain, unmarked packaging.