What is it?
What Testolone is
1Testolone is the common marketplace name for RAD140, also listed as vosilasarm. It is a nonsteroidal selective androgen receptor modulator, or SARM, developed as an investigational drug-like compound rather than a dietary supplement ingredient.
Names, aliases and forms
Mechanisms of action
Mechanism context
2RAD140 was designed to bind androgen receptors and produce tissue-selective androgenic signaling. Preclinical work describes anabolic androgen action models, and the Phase 1 study tracked SHBG and PSA as markers of androgen receptor engagement. Mechanism should not be read as proof of consumer performance or cognitive benefit.
Potential effects and evidence map
RAD140 has preclinical SARM research and a first-in-human Phase 1 study in postmenopausal women with ER+/HER2- metastatic breast cancer. That study reported once-daily dose levels, androgen receptor engagement markers, a 44.7-hour The time for blood levels to fall by half during the final elimination phase.Source, and frequent treatment-emergent adverse events including liver enzyme and bilirubin elevations. This is not evidence for healthy-user cognition, strength, or supplement-style cycle claims.
RAD140 has preclinical anabolic androgen receptor research, but public human evidence does not establish healthy-user strength, endurance, or performance benefits.
No reliable human evidence was found that Testolone/RAD140 improves focus, attention, memory, mood, or nootropic outcomes.
Androgen receptor engagement markers in an oncology study do not establish consumer libido or vitality benefits.
Typical dosages and timing
In 22 postmenopausal women with metastatic breast cancer, the Phase 1 study evaluated 50, 100, and 150 mg once daily; the maximum tolerated dose in that protocol was 100 mg/day. These are oncology research doses, not a safe consumer range. No evidence-based healthy-adult supplement dose or cycle has been established.
Timing & effect horizon
Safety, side effects and risk profile
As of 14 October 2026, U.S. FDA states SARMs cannot legally be marketed as dietary supplements or approved drugs. Separate WADA anti-doping restrictions apply in governed sport.
Serious liver injury has been reported after oral RAD140 use in previously healthy adults. Its frequency is unknown, and case reports cannot fully separate compound toxicity from product quality.
FDA warns that SARM-containing bodybuilding products may increase risk of heart attack or stroke.
FDA SARM warnings include sexual dysfunction, infertility, and testicular shrinkage. The incidence and reversibility of these outcomes specifically with RAD140 are not established.
Interactions and stacking safety are insufficiently characterized. Oncology-trial medication exclusions do not prove specific drug interactions.
FDA lists pregnancy miscarriage among SARM-associated concerns; lactation safety is unestablished. These are special-population cautions, separate from the overall adult risk assessment.
Healthy-user efficacy, nootropic effects, consumer dosing, cycle design, and long-term safety remain unsupported or unclear in the public evidence checked.
A published case describes a previously healthy 24-year-old man with jaundice and liver injury after five weeks of oral RAD140 use. Improvement followed discontinuation, but recovery can be prolonged. Case reports cannot estimate incidence or prove product purity. Separately, the oncology trial reported frequent liver-test abnormalities at higher doses in heavily pretreated patients; those rates do not describe healthy consumers.
High risk reflects FDA warnings about serious harm from consumer SARM use, reinforced by RAD140 liver-injury reports in previously healthy adults. Moderate would understate the potential severity and prolonged recovery. Critical is not supported because the likelihood of catastrophic harm at any defined consumer dose is unknown. This is a qualitative assessment, not an incidence estimate; no typical safe oral dose or duration has been established. Pregnancy, medication interactions, and product contamination remain separate cautions.
Interactions and cautions
The oncology protocol restricted several concurrent medicines and hormone-active agents. Such exclusions protect study interpretation and participants; they do not establish a validated interaction list. There is no reliable evidence that bodybuilding stacks or post-cycle regimens make RAD140 use safe.
Legal and regulatory status
As of 14 October 2026, U.S. FDA states that SARMs cannot legally be marketed as dietary supplements or drugs and describes them as unapproved drugs, including products labeled for research use only. This U.S. marketing position does not settle possession or import rules in other jurisdictions.
As of 14 October 2026, USADA guidance identifies RAD140/Testolone as a SARM and states that SARMs are prohibited at all times under WADA category S1.2. This applies to athletes governed by WADA-based rules, in and out of competition.
Practical buying and quality notes
- A label of 10 mg per capsule and 60 capsules implies 600 mg of labeled RAD140 per pack; that arithmetic does not confirm actual content or a safe dose. Compare pack price only after checking currency, pack count and ingredient amount. The two currently linked capsule records have inconsistent prices, so confirm the live retailer price before making a value comparison.9
- A 2017 analysis of internet products marketed as SARMs found frequent identity and label-amount discrepancies. It did not test the current linked offers. A useful certificate of analysis (COA) should identify the matching batch, laboratory, substance and measured concentration; a generic purity claim does not establish clinical safety or legal status.9
FAQ
Is Testolone the same as RAD140?
1Yes. Testolone is the common marketplace name for RAD140, and PubChem also lists vosilasarm among RAD140 synonyms. Product labels may use RAD140, RAD-140, Testolone, or vosilasarm, so identity testing matters.
What is the Testolone dosage?
2There is no validated healthy-user dosage. The oncology doses described above are research context, not bodybuilding or nootropic guidance; a capsule label is not evidence of safety.
Does the half-life establish a cycle length?
2No. Plasma half-life describes drug elimination, not useful effect duration, endocrine recovery, or a validated cycle. Healthy-user onset, duration and cycle timing remain unestablished.
Can athletes use RAD140?
7RAD140 is prohibited at all times for athletes governed by WADA-based rules, according to USADA guidance checked on 14 October 2026. A research-use label does not remove that anti-doping restriction.
Is Testolone legal to buy?
6Online availability is not legal approval. As of 14 October 2026, U.S. FDA states SARMs cannot legally be marketed as dietary supplements or drugs. Import, possession and product rules can differ elsewhere.
References
- PubChem Compound Summary for RAD140/Testolone/Vosilasarm, CID 44200882.
- LoRusso P, Hamilton E, Ma C, et al. A First-in-Human Phase 1 Study of a Novel Selective Androgen Receptor Modulator (SARM), RAD140, in ER+/HER2- Metastatic Breast Cancer. Clinical Breast Cancer. 2022;22(1):67-77.
- ClinicalTrials.gov record NCT03088527. Phase 1, First-in-Human Study of RAD140 in Postmenopausal Women With Breast Cancer.
- Miller CP, Shomali M, Lyttle CR, et al. Design, Synthesis, and Preclinical Characterization of the Selective Androgen Receptor Modulator (SARM) RAD140. ACS Medicinal Chemistry Letters. 2011;2(2):124-129.
- Yu Z, He S, Wang D, et al. Selective Androgen Receptor Modulator RAD140 Inhibits the Growth of Androgen/Estrogen Receptor-Positive Breast Cancer Models with a Distinct Mechanism of Action. Clinical Cancer Research. 2017;23(24):7608-7620.
- U.S. FDA. FDA Warns of Use of Selective Androgen Receptor Modulators (SARMs) Among Teens, Young Adults. Accessed 14 October 2026.
- U.S. Anti-Doping Agency. What Athletes Need to Know about Selective Androgen Receptor Modulators (SARMs).
- RAD-140 Drug-Induced Liver Injury. Ochsner Journal. 2022. PMID: 36561105.
- Van Wagoner RM et al. Chemical Composition and Labeling of Substances Marketed as Selective Androgen Receptor Modulators and Sold via the Internet. JAMA. 2017. PMID: 29183075.