Not FDA-approved for human use. WADA-banned for tested athletes. Sold as a research chemical; clinical safety beyond short-term trials is not established. This page is educational reference only, not a recommendation or endorsement of use.
- Half-life
- 60 h
- Route
- Oral
Summary
RAD-140 has high binding affinity at the androgen receptor. Developed by Radius Health (RAD = Radius), it reached Phase I clinical trials for breast cancer treatment before development slowed. User reporting describes a heavier side-effect profile than Ostarine, particularly for HPTA suppression, lipids, and mood.
Legal status: Not FDA-approved. WADA-prohibited at all times in competitive sport. Sold as a research chemical outside of approved channels.
Main effects
- Substantial lean mass accretion — more dose-responsive than Ostarine in user-reported bloodwork
- Significant strength gains, commonly reported by users
- Increased aggression / drive (can be positive or problematic)
- Hardness / density in physique (anecdotal)
- Minimal water retention
- Does not aromatize to estrogen
Common side effects
- HPTA suppression — substantial. Total testosterone reductions of 50–70% are commonly reported on cycle; recovery typically takes 2–4 months after discontinuation.
- Lipid changes — notable HDL drops (30–50% reductions documented in user bloodwork). LDL elevation also common.
- Hepatic enzymes — ALT/AST elevations more pronounced than Ostarine.
- Mood / aggression — increased aggression and irritability commonly reported; some users discontinue for this reason.
- Sleep disruption — insomnia or restless sleep, especially with evening administration.
- Testicular ache — mild discomfort presumably from HPTA suppression.
- Headaches — reported by some users, mechanism unclear.
- WADA-banned — detectable on standard doping tests for 2–3 weeks.
- Drug-induced liver injury (case report) — Barbara et al. (2022) described DILI in a young man taking RAD-140; isolated case but worth knowing.
Mechanism
High-affinity androgen receptor agonist with strong tissue selectivity for muscle. In animal studies showed neuroprotective effects against testosterone-induced apoptosis in neurons (one reason it was studied for Alzheimer's-related muscle wasting in men).
Anabolic-to-androgenic ratio in preclinical studies: approximately 90:1.
Pharmacokinetics
- Half-life: ~60 hours (some sources cite 16–20 hours; the longer figure is from animal data and matches user-reported administration cadence)
- Tmax (oral): ~3 hours
- Bioavailability (oral): moderate to high in animal models; human data limited
- Metabolism: hepatic
- Elimination: urinary; detectable on WADA testing for 2–3 weeks
Bloodwork monitoring
Standard panel coverage seen in harm-reduction discussions and user case reports:
- Total + Free Testosterone
- LH, FSH
- Estradiol (sensitive assay)
- Full lipid panel (especially HDL)
- ALT, AST, GGT
- CBC
Interactions
RAD-140 acts at the same receptor as testosterone and other androgen receptor agonists, so suppression of LH and FSH reflects total androgenic signaling rather than any single agent. Its effect on HDL is among the more pronounced documented in the class, and other exposures that lower HDL act on the same marker, so a lipid change cannot be attributed to one compound in isolation.
Pharmacokinetic modeling parameters
ka: 0.8 /day
ke: 0.28 /day
Vd: 60 L
F: 0.70
half_life_hours: 60
Notes and caveats
- Animal studies showed dose-dependent hepatotoxicity at higher exposures. Human safety profile is still being clarified through user case reports rather than controlled trials.
- The "feel" is noticeably different from milder SARMs — users often describe a stim-like edge.
- A 2022 case report (Barbara et al.) described drug-induced liver injury in a young man taking RAD-140; isolated case but worth knowing.