Testolone (RAD-140)
Testolone (RAD-140) is a potent non-steroidal SARM originally explored for breast cancer and muscle wasting. Human data are minimal, limited largely to an early oncology trial, so most claims are preclinical or anecdotal. Recreational users report strong strength and size gains alongside marked testosterone suppression, and case reports link it to liver injury.
01 Overview
RAD-140 was developed by Radius Health as a high-affinity androgen-receptor agonist, with a small oncology trial (RAD140 in AR-positive breast cancer) providing most of the limited human exposure data. Preclinical studies show robust anabolic and neuroprotective activity, but efficacy for physique or performance in humans is not established.
Among SARMs, RAD-140 is regarded anecdotally as one of the more potent and more suppressive. It is prohibited in sport, unapproved as a medicine, and has been named in published cases of drug-induced liver injury. All recreational dosing is extrapolated from anecdote rather than trials.
02 Mechanism
High-affinity selective androgen-receptor agonist with strong anabolic signalling in muscle and preclinical neuroprotective effects.
03 Dosing
| Tier | Dose | Route | Notes |
|---|---|---|---|
| Light | 5–10 mg/day | Oral | Anecdotal starting range; no validated human dose exists. |
| Common | 10–20 mg/day | Oral | Higher anecdotal range associated with stronger suppression. |
Ester comparison
| Ester | Half-life | Injection freq. | Testosterone by mass |
|---|
04 Effects
| Effect | Magnitude | Evidence | |
|---|---|---|---|
| Increased muscle mass and strengthWidely reported by users; not demonstrated in controlled physique trials. | Anecdotal | ||
| Anabolic activity in muscleAnimal studies show significant increases in lean mass and androgen-receptor activation. | Preclinical | ||
| Neuroprotective activityCell and animal models suggest neuroprotective effects; unproven in humans. | Preclinical |
05 Side effects
| Effect | Severity | Frequency | Evidence | Countermeasures |
|---|---|---|---|---|
| Testosterone suppressionReported as markedly suppressive of endogenous testosterone, often requiring longer recovery than milder SARMs. | Severe | Near-universal | Anecdotal | |
| HepatotoxicityPublished case reports describe severe drug-induced liver injury attributed to RAD-140. | Severe | Uncommon | Observational | |
| Lipid changes (HDL reduction)Users commonly report reduced HDL; not quantified in controlled human data. | Moderate | Common | Anecdotal |