Masteron (Drostanolone)
Drostanolone, 2α-methyl-DHT derivative injectable AAS. Originally FDA-approved (Drolban, Lilly 1959) for inoperable breast cancer in postmenopausal women; today underground market only. Classic "hardening" cutting steroid.
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WHAT IS MASTERON (DROSTANOLONE)?
Detailed overview
Masteron (Drostanolone) is a 2α-methyl-dihydrotestosterone derivative, jointly synthesized by Syntex and Eli Lilly in 1959 and FDA-approved in 1961 under the brand Drolban for palliative treatment of inoperable, postmenopausal breast cancer. Displaced by modern tamoxifen-based therapy; Lilly discontinued in 1993. Anabolic:androgenic ratio ~62:25 (low anabolic, moderate androgenic). The 2α-methyl group blocks both 5α-reductase and aromatase activity – does NOT convert to estrogen and exhibits unique mild aromatase-inhibitor effect (Bhasin 2018 reference AAS classification). NOT 17α-alkylated, so hepatotoxicity is minimal. In the bodybuilding context, the classic cutting steroid used to achieve "hardness" and vascular esthetics, often in the last 6-8 weeks of contest prep. WADA-banned year-round.
Mechanism
AR agonist, 2α-methyl-DHT, NOT aromatized
Anabolic:Androgenic
62:25
Half-life
2-3 d (Prop), 7-10 d (Enan)
Onset
24-72 h (IM ester)
Legal status
Discontinued Rx, UGL only. WADA-banned.
Data console
Lab data
Safety
Side effects, stop signs, contraindications
Side effects · 7
- Acceleration of androgenetic hair loss: drostanolone is structurally 2α-methyl-DHT and directly activates the hair-follicle androgen receptor, triggering irreversible miniaturization in genetically predisposed users (finasteride does NOT protect, as the molecule is already 5α-reduced).
- Virilization in women: voice deepening, hirsutism, clitoral enlargement, menstrual disruption – may be IRREVERSIBLE even after a single cycle, hence strictly contraindicated in women.
- Adverse lipid profile: drop in HDL cholesterol (typically 20-30%) and rise in LDL, increasing atherosclerosis and cardiovascular-event risk with prolonged use.
- HPTA suppression: shutdown of endogenous testosterone production, reduced LH/FSH, testicular atrophy and impaired fertility; prolonged AAS exposure can cause persistent secondary hypogonadism, requiring PCT.
- Prostate androgen stimulation: as a DHT analog it activates prostate androgen receptors, which can cause prostate enlargement and urinary symptoms, and may accelerate growth of a pre-existing androgen-dependent prostate tumor.
- Androgenic skin effects and behavioral symptoms: increased sebum production, acne, plus heightened irritability/aggression; chronic AAS use can lead to psychological dependence.
- Injection-site reaction (PIP): especially with the Propionate variant the alcohol-containing oil vehicle is often painful, causing 24-48 h swelling and inflammation; non-sterile technique can cause abscess/infection.
Contraindications · 7
- Use in women (especially during pregnancy/breastfeeding): absolutely contraindicated due to the risk of virilization and fetal masculinization.
- Prostate carcinoma or male breast carcinoma, and significant benign prostatic hyperplasia (BPH) – androgen stimulation can worsen the condition.
- Family history of androgenetic alopecia / DHT-sensitive scalp: as a DHT derivative it accelerates irreversible hair thinning.
- Existing cardiovascular disease or high risk (atherosclerosis, uncontrolled hypertension, adverse baseline lipids – e.g. LDL >130 mg/dL or HDL <40 mg/dL).
- Active fertility plans / treated male infertility: AAS suppress spermatogenesis and the HPTA axis.
- Anticoagulant therapy (e.g. warfarin): Masteron can potentiate the anticoagulant effect, contraindicated without close INR monitoring.
- Adolescents / incompletely developed skeleton: androgens can cause premature epiphyseal closure and stunted height.
Related Performance Compounds
Same therapeutic category
Studies
Related research and clinical findings
Adverse health consequences of performance-enhancing drugs: an Endocrine Society scientific statement
Pope HG Jr, Wood RI, Rogol A, Nyberg F, Bowers L, Bhasin S.
Testosterone therapy in men with hypogonadism: an Endocrine Society clinical practice guideline
Bhasin S, Brito JP, Cunningham GR et al.
Effects of androgenic-anabolic steroids in athletes
Hartgens F, Kuipers H.
Metabolism of anabolic androgenic steroids
Schänzer W.
Anabolic-androgenic steroid dependence: an emerging disorder
Kanayama G, Brower KJ, Wood RI, Hudson JI, Pope HG Jr.
Long-term combined administration of dromostanolone propionate (Mastisol) and cyclophosphamide for advanced breast cancer
Nomura Y, Hattori T, Abe Y.
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The information here is for educational and scientific purposes only. Performance-enhancing compounds (AAS, prohormones, stimulants, doping agents) are illegal without prescription in Hungary and most of the EU, and carry serious health and legal risks. WADA bans them in competitive sport. This is NOT a usage guide, and we do not encourage any illegal use. If you do use them, medical supervision and regular bloodwork are ESSENTIAL. Severe endocrine, cardiovascular, hepatic and psychiatric side effects are possible.