RU58841

RU-58841 · PSK-3841 · HMR-3841

Ancillary aas TRT Topical Animal Data / Community

Half-life

6 hr

Time to Peak

2 hr

Steady State

~2 days

Dose Range

25–75 mg

Frequency

Daily

Overview

Experimental non-steroidal anti-androgen applied topically to the scalp. Developed in the 1990s by Roussel Uclaf (hence "RU") for androgen-mediated alopecia — discontinued due to systemic absorption concerns in clinical trials. The TRT and AAS community uses it as a topical scalp treatment to prevent DHT-mediated hair follicle miniaturisation without systemic anti-androgenic effects. Rationale: Blocks androgen receptor at the scalp follicle without significantly blocking AR elsewhere in the body (lower finasteride-like sexual side effects). Harm reduction: Systemic absorption can occur — possible partial systemic anti-androgenic effect. Some community members report libido changes. No long-term safety data in humans. Research compound — not pharmaceutically regulated. Quality control of purchased product is a significant concern.

Mechanism of Action

Competitive, non-steroidal androgen receptor antagonist (type II). Applied topically to scalp — intended to block DHT binding to AR in hair follicles without significant systemic distribution. Some systemic absorption occurs despite topical application — mechanism not fully restricted to scalp.

Dosing Information

Route Dose Range Half-life Tmax Frequency
Topical 25–75 mg 6 hr 2 hr Daily

Storage & Handling

Refrigerated — Store at 4C or below. Dissolve in ethanol/propylene glycol carrier. Use within 3–6 months of preparation. Protect from light.

Used in Regimens

RU58841 is not currently part of any catalog regimen.

Data Sources

  • Community r/steroids Compound Experience Directory

Related Tools

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Doseline provides informational tools only. It is not a medical device and does not provide medical advice. Always consult a qualified healthcare provider.