Description
Methenolone Enanthate (Primobolan, Primo, Primobolan Depot) is the injectable enanthate ester variant of a 5α-reduced DHT derivative. The substance has been used in human medicine since the 1960s and is still approved in some countries for treatment of premature-birth-related anemia and muscle wasting.
Per study reports Methenolone binds weakly to moderately to the androgen receptor. The substance doesn’t aromatize to estradiol, excluding water retention and estrogen-mediated effects. Anabolic action is mild - comparable to Anavar in potency, but as injection with better pharmacokinetic profile.
The enanthate ester form has a half-life of about 10-14 days, allowing once- to biweekly injections. Steady-state is established after 3-4 weeks. The injectable form has substantially higher bioavailability compared to the oral variant, making Primobolan E more economically attractive.
In recreational research practice Primobolan E is classically positioned as “women’s compound” due to the extremely mild profile. Also in men’s research setups Primo is popular as TRT accompanying compound or in cutting phases.
Known effects in studies: low hepatotoxicity (no 17α-methyl), no aromatization, mild HPG suppression, low lipid profile risk. One of the “cleanest” anabolics in the class.
Methenolone is on the WADA banned list.
You can order Methenolone Enanthate as an oily injection solution in 10-pack at 200mg/ml.
This information is for research and educational purposes only. No medical recommendations.
Risks & Safety
Methenolone Enanthate is considered one of the mildest anabolics in its class - the effects described in the literature are low, but even a “clean” anabolic intervenes in the hormonal system.
Documented in studies and the application literature:
- No aromatization: the 5-alpha-reduced DHT derivative does not aromatize to estradiol, water retention and estrogen-mediated effects are not documented.
- Mild androgenic effects: as a DHT derivative, acne and accelerated hair loss with genetic predisposition are documented, the androgenic profile is mild overall.
- Suppression of endogenous production: Methenolone mildly suppresses the HPG axis. Reduced endogenous testosterone production is documented, a test base is customary in research practice.
- Cardiovascular: the literature describes a lipid profile risk that is low for the class, yet cardiac effects with long-term use are documented. Hepatotoxicity is low because there is no 17-alpha-methyl group.
Baseline bloodwork before, during and after a research protocol is strongly advised. This classification does not replace medical advice. Risk and responsibility for any actual use lie entirely with the buyer.
Studies
- Effect of methenolone enanthate (NSC-64967) in advanced cancer of the breast - Cancer 1968: clinical oncology study of methenolone enanthate in advanced breast cancer.
- Treatment of Refractory Anemias with Methenolone - Acta Medica Scandinavica 1979: clinical study on the erythropoiesis-stimulating effect in refractory anemias.
- Treatment of Aplastic Anaemia with Methenolone - Acta Haematologica 2009: more recent clinical study on methenolone in aplastic anemia.
- Detection and quantitation of the major urinary metabolite of methenolone acetate by isotope dilution mass spectrometry - Journal of Steroid Biochemistry 1983: classic doping-detection study on the methenolone metabolites.
- Studies on anabolic steroids - 4. Identification of new urinary metabolites of methenolone acetate in human by gas chromatography/mass spectrometry - J Steroid Biochem Mol Biol 1990, Goudreault et al: further characterization of the metabolism pathways.
