Compound profile
Methenolone
Also known as Primobolan, Primo, Methenolone enanthate, Methenolone acetate
Last reviewed October 2026
Educational only. A summary of published research, not medical advice or a recommendation. No doses are listed.
Quick take
A DHT-derived steroid, injected or taken as a tablet, often described by users as mild, though it still shuts down natural testosterone and worsens cholesterol.
- Class
- Anabolic steroids
- Status
- Not approved
- Evidence
- Early or small human studies
- Half-life
- Not well documented
Mechanism fingerprint
What it acts on, and how. Each chip links to that pathway on the map.
A DHT derivative that doesn't convert to estrogen. Unlike most oral steroids, the tablet form isn't 17α-alkylated.
What makes it different
A DHT derivative whose tablet form isn't 17α-alkylated, unlike most oral steroids.
Compare side by side
Mechanism & pathways
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Agonist
Androgen receptor
Receptor for testosterone and DHT. Activating it builds muscle and drives male traits such as body hair and a deeper voice. Every anabolic steroid binds it.
Evidence overview
Early or small human studies
Older clinical use and studies outside the US; no modern trials.
A breakdown into human, animal and cell studies hasn't been added for this compound yet.
Why it's used
Medically, it was used in some countries for muscle wasting and anemia. Bodybuilders use it for slow, lean gains without estrogen-related side effects such as water retention.
Side effects & risks
Reported side effects
- Hair loss in people prone to it
- Acne
- Lower HDL (“good”) cholesterol
Risks and warnings
- Shuts down the body's own testosterone production: testicles shrink and sperm counts fall, and recovery after stopping can take months or be incomplete.
- Lowers HDL (“good”) cholesterol and raises LDL, adding to heart disease risk.
- Long-term use is linked to high blood pressure, heart muscle damage (cardiomyopathy), heart attacks and early death.
- In women: masculinizing effects (deeper voice, facial and body hair, clitoral enlargement) that can be permanent.
- Underground-lab products are often mislabeled or contaminated, and non-sterile injections can cause abscesses and infections.
- Schedule III controlled substance in the US: illegal to possess without a prescription.
- Prohibited in sport by the World Anti-Doping Agency (WADA).
FAQ
Short answers taken from this profile.
What is Methenolone?
A DHT-derived steroid, injected or taken as a tablet, often described by users as mild, though it still shuts down natural testosterone and worsens cholesterol.
How does Methenolone work?
A DHT derivative that doesn't convert to estrogen. Unlike most oral steroids, the tablet form isn't 17α-alkylated.
What receptors or pathways does Methenolone act on?
androgen receptor (agonist).
How is Methenolone different from similar compounds?
A DHT derivative whose tablet form isn't 17α-alkylated, unlike most oral steroids.
Is Methenolone approved?
Never approved in the US; sold as a prescription medicine in some other countries in the past.
What has Methenolone been studied for?
Medically, it was used in some countries for muscle wasting and anemia. Bodybuilders use it for slow, lean gains without estrogen-related side effects such as water retention.
How strong is the evidence?
Early or small human studies. Older clinical use and studies outside the US; no modern trials.
What are the main risks?
Shuts down the body's own testosterone production: testicles shrink and sperm counts fall, and recovery after stopping can take months or be incomplete. Lowers HDL (“good”) cholesterol and raises LDL, adding to heart disease risk. Long-term use is linked to high blood pressure, heart muscle damage (cardiomyopathy), heart attacks and early death. More are listed under risks and warnings.
Sources
- Kicman AT. Pharmacology of anabolic steroids. Br J Pharmacol 2008.
- Pope HG et al. Adverse health consequences of performance-enhancing drugs: an Endocrine Society scientific statement. Endocr Rev 2014.