AC-262,536: The Underground SARM You’re About to Hear A Lot More About
There’s a good chance you’ve never heard of AC-262,536 — or if you have, it probably came up in some obscure Reddit thread or whispered in a hardcore gym circle. It’s not as mainstream as RAD-140 or LGD-4033, but it’s starting to make waves in the enhanced bodybuilding world. Why? Because this lesser-known SARM may offer a surprising combo: anabolic strength with potentially lower suppression.
In this article, we’re breaking down what AC-262 actually is, how it works in the body, what the science (and bro-science) says about it, and whether it’s worth running in your next cycle. Fully humanized, no BS, and backed by actual science where it exists — and honest real-world experience where it doesn’t.
🔬 What Is AC-262,536?
AC-262,536 is a nonsteroidal selective androgen receptor modulator (SARM) developed by Acadia Pharmaceuticals. Unlike more well-known SARMs, AC-262 was never pushed far into clinical development. It’s remained mostly in preclinical phases, which makes it a bit of a “ghost” compound in the pharma world — but that’s part of why underground biohackers and bodybuilders are intrigued by it.
It was initially developed as a therapeutic compound aimed at muscle wasting and potentially neurodegenerative conditions. While it hasn’t seen the level of formal attention that compounds like Ostarine (MK-2866) have, AC-262 caught attention for its interesting anabolic profile and a potentially lighter side-effect load.
🧠 How It Works
Like other SARMs, AC-262,536 selectively binds to androgen receptors in skeletal muscle and bone tissue. But what makes it different is how it modulates those receptors.
In preclinical studies, AC-262 was shown to:
- Stimulate anabolic activity in muscle tissue
- Avoid binding significantly to androgen receptors in the prostate and seminal vesicles (meaning less androgenic side effects)
- Have neuroprotective potential through androgen receptor-mediated pathways in the brain
That last point is important. AC-262 may have benefits beyond the gym — like improved cognitive function, mood, or resilience against stress, although that’s still speculative based on animal data.
Binding Affinity & Selectivity
Its binding affinity is lower than that of RAD-140 or LGD-4033, but it seems to activate the receptor in a way that still drives gains without triggering as much suppression. It’s sometimes described as a “mild but clean” SARM.
🧪 Dosage & Half-Life
Since AC-262,536 hasn’t made it to full human trials, dosages are based largely on rat studies and anecdotal reports from users. But here’s what we know:
Common Dosage Range (anecdotally):
- 10mg to 30mg per day appears to be the sweet spot
- Beginners typically start with 10–15mg/day
- Advanced users often push 20–30mg/day, split into two doses
Half-Life:
- Estimated to be around 6–8 hours, meaning twice-daily dosing is preferred for stable plasma levels
Compared to longer-lasting SARMs like LGD-4033 or Ostarine, AC-262 needs more frequent dosing — but that’s manageable if you’re running a serious cycle.
💪 What It’s Capable Of (Realistic Gains)
Don’t expect AC-262 to turn you into a monster overnight. This isn’t Tren or even RAD-140. What you can expect is more subtle, steady progress — but without the heavy shutdown or bloating.
Reported Benefits:
- Lean muscle gain (2–5 lbs in 6–8 weeks)
- Improved muscular endurance
- Mild strength increase
- Enhanced vascularity and muscle “hardness”
- No water retention
Who Is This Best For?
- Beginners looking for a “low-risk” entry SARM
- Enhanced lifters in between heavier cycles (bridge compound)
- Recomp or maintenance phases where recovery and lean preservation matter
Some users compare it to a slightly more anabolic version of Ostarine but with less suppression than RAD-140.
🔄 Stackability
AC-262 isn’t typically run solo by advanced lifters, but it plays well in stacks.
Common Stacks:
- AC-262 + MK-677 (great for recovery and GH synergy)
- AC-262 + GW-501516 (cutting stack: endurance + fat loss)
- AC-262 + S4 (Andarine) (visual hardness + moderate size gains)
Because suppression is minimal, AC-262 also works well in bridge cycles — used during the “off” period between full suppression runs.
😬 Side Effects
This is where AC-262 starts to shine. Based on what’s been reported, side effects are minimal — and in some cases, nonexistent.
Potential Side Effects:
- Mild testosterone suppression (usually after 4–6 weeks)
- Possible fatigue in some users when dosed too high
- Temporary decrease in libido (rare, and usually dose-related)
Unlike harsher SARMs, AC-262 has shown little to no impact on:
- Estrogen levels
- Liver enzymes (though bloodwork is always recommended)
- Blood pressure or cholesterol in moderate dosing windows
That said, always get pre- and post-cycle bloodwork. Individual reactions vary.
🤕 Is PCT Needed?
Probably — but not always.
Most users who run short cycles (4–6 weeks) at lower doses (10–15mg) report minimal shutdown. Some recover naturally within 2–3 weeks post-cycle. However:
If you:
- Run 8+ weeks
- Use 20mg+ daily
- Stack with suppressive compounds
…then a mild PCT is smart.
Recommended PCT (if needed):
- Clomid 25mg/day for 2–3 weeks
- Or Nolvadex 20mg/day for 3 weeks
Some users also use natural test boosters like Tongkat Ali, Fadogia Agrestis, or DHEA post-cycle for added recovery — especially if no pharmaceutical PCT is planned.
📈 Real World Feedback: What Lifters Are Saying
We scoured forums, Reddit threads, and Discord groups to compile actual AC-262 experiences:
“Ran 20mg/day for 6 weeks during a cut. Dropped 6lbs fat, gained 3 lbs lean mass. No suppression, no crash.”
“I like it as a bridge. Keeps you dry and tight. Pumps aren’t insane but consistent. I’d compare it to mild Anavar in feel.”
“Strength was up slightly by week 3. Didn’t feel stimmed out or flat. Libido stayed solid.”
“Didn’t notice much at 10mg. Bumped to 25mg — better pumps and better endurance. Next time will stack with MK.”
Notably, very few users report major suppression or side effects, even after 6–8 week cycles.
⚖️ Legality and Sourcing
AC-262, like most SARMs, is sold legally in many countries as a research chemical. It is not approved by the FDA for human use and is banned in competitive sports under WADA regulations.
Because it’s not mainstream, sourcing can be tricky:
- Many vendors don’t carry it consistently
- Lab testing is crucial — purity can vary dramatically
- Expect higher cost per mg due to low demand and production volume
Always look for third-party lab tests, batch documentation, and sourcing reviews before you buy.
✅ Final Verdict: Worth It or Waste?
If you’re looking for a mild, clean, anabolic compound that can:
- Deliver moderate lean gains
- Preserve muscle during cuts
- Bridge cycles without deep suppression
…then AC-262,536 is absolutely worth considering.
It’s not a miracle drug. It’s not going to match RAD-140 in raw aggression or LGD-4033 in mass. But if you want a compound that does its job quietly, efficiently, and with minimal side effects — AC-262 punches above its weight.
Best Use Case: Lean maintenance or cutting stack for intermediate users, or intro compound for first-timers.
If you can find a quality source, AC-262 is one of the most underrated SARMs in the game right now.
