RAD-140 (Testolone)

RAD-140, also called Testolone, is a selective androgen receptor modulator (SARM). It was developed by Radius Health, originally with a focus on neuroprotective properties and oncology questions. In performance research it is regarded as one of the strongest members of its class.

It is not a steroid but a small, orally available molecule. The appeal: hit the androgen receptor in muscle and bone without acting broadly where classic steroids cause trouble. How well that selectivity holds up across every endpoint is an open research question.

RAD-140 binds the androgen receptor and activates it with tissue preference: strong in muscle and bone, weaker in tissues like prostate or sebaceous glands. In preclinical models it showed a very high anabolic-to-androgenic ratio (over 90:1 in the original characterization).

Unlike testosterone, RAD-140 does not aromatize to estrogen and is not reduced to DHT. That changes the side-effect pattern but does not remove it, in particular the suppression of the body's own testosterone production remains.

RAD-140 is taken orally, no mixing, no injecting.

• Once daily, the roughly 20-hour half-life means one dose is enough.
• With some water, with or without food.
• Research cycles typically run over 8 weeks, followed by a break and axis recovery.

The original characterization (Miller, 2011) described RAD-140 as a potent, orally available SARM with a very high anabolic-to-androgenic ratio. A preclinical study (Yu, 2017) showed RAD-140 inhibits the growth of certain androgen-receptor-positive breast cancer models, the original oncology development track.

On the risk side, RAD-140 is the SARM with the densest case literature on liver injury. A cleanly documented case of liver injury under RAD-140 was published in 2023 (Ladna). There are no human efficacy studies for muscle building in healthy people, and no approval exists.

Documented in studies and case reports:

• Suppression of the body's own testosterone axis, dose-dependent, with recovery times of weeks.
• Falling HDL values, shifts in the lipid profile.
• Liver values: RAD-140 has the densest liver-injury case literature among SARMs, monitoring here is not optional.
• Anecdotally: irritability, aggression, sleep issues at higher doses.

• Start low, 10mg is usually enough, do not chase the upper end.
• Limit cycles (often 8 weeks) and plan a real break afterwards.
• In official competition RAD-140 is banned and detectable in urine for weeks (WADA S1.2).
• Liver and blood values before and after a cycle make sense.

Store dry, cool and protected from light, out of reach of children. Keep the original container closed and mind the expiry date.