11ketotestosterone, 4 weeks to 200 mg per day, according to you needs a serm? Or ok pct otc, example KingdbloodsHaven't used s4 but would need a PCT. Whether it needs a SERM would depend on dose and your biology. I would say either SERM or bloods but even if you go for bloods, you should have SERM ready in case bloods indicate a need for it.
S4 is slightly suppressive (less than ostarine) but for any suppressive compound going with just OTC PTC is risky.
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