Metenolone enanthate (methenolone) 100 mg/mL

Basic Info

CAS Number	303-42-4
Active Ingredient	Methenolone (metenolone), the 17-heptanoate (enanthate) ester of 1-methyl-5α-androst-1-en-3-one
Dosage Form	Oil vial
Specification & Packaging	Strength: 100 mg/mL Pack: 1 × 10 mL vial Group: 02 Item No.: 22

Storage & Common Excipients

Storage Conditions	Tightly closed, protected from light, 15–25 °C. Some suppliers specify 2–8 °C — follow the label, as refrigeration may cause precipitation
Common Excipients	Typical oil formulation: castor/sunflower oil, polysorbate 80, benzyl alcohol, benzyl benzoate, edetate disodium; confirm against COA

Product Introduction

The active ingredient of the original Primobolan Depot, an anabolic–androgenic steroid ester. It remains compendial in some pharmacopoeias as an oil injection

Therapeutic Use

Haematological indications such as aplastic anaemia in historical labelling; as an anabolic agent in some countries for wasting and post-surgical recovery. Most markets have withdrawn the human indication

Mode of Action

1-diene structure with comparatively strong anabolic and milder androgenic activity; partially aromatisable to oestradiol

Administration & Monitoring

As prescribed; rule out prostate and breast cancer before use; monitor full blood count (Hb/ANC/PLT if for aplastic anaemia), lipids, liver function and PSA

Important Safety Information

An anabolic steroid and controlled substance; non-medical use is unlawful. Animal-derived lipid excipients carry BSE/TSE risk — compliant sourcing is required

Adverse Reactions

Injection-site reactions; acne, hirsutism, voice deepening in women, menstrual disturbance; raised transaminases, dyslipidaemia and reduced HDL; raised PSA and testicular atrophy in men; prolonged abuse may cause myocardial hypertrophy and bone-marrow suppression

Important Risks

Cardiovascular (worsening lipids, polycythaemia, left-ventricular hypertrophy), hepatotoxicity, reproductive suppression, tumour-promotion risk; dependence and withdrawal with low testosterone

Contraindications

Pregnancy and lactation; known or suspected prostate or breast cancer; severe hepatic or renal impairment; children and adolescents with open epiphyses

Special Populations

Contraindicated in children and adolescents; prostate and cardiovascular assessment for older males; consider effects on spermatogenesis in men of childbearing potential

Usage Limitations

Prohibited in competitive sport (WADA Prohibited List); prescription and controlled-substance storage and record-keeping required; no resale or repackaging

Anti-Doping Testing

WADA Prohibited List S1.1; targets methenolone and its 5α-methenolone metabolite, detected in urine by GC-MS/MS and LC-MS/MS

Product Quality Testing

Identification (HPLC/MS), assay/content uniformity, related substances, clarity and particulate matter, fill volume, sterility and endotoxin, residual solvents, stability; excipients require documented BSE/TSE compliance; COA