Drostanolone Propionate (Masteron)
A DHT-derived, non-aromatising injectable (2-alpha-methyl-dihydrotestosterone) historically used to treat breast cancer for its anti-oestrogenic effect. In bodybuilding it is valued for a hard, dry, defined look near contest time rather than raw mass, with a short propionate ester requiring frequent injection. Androgenic side effects (hair loss, acne) predominate; oestrogenic effects are essentially absent.
01 Overview
Drostanolone is dihydrotestosterone with a 2-alpha-methyl group that increases anabolic potency and metabolic stability. It was marketed as Masteron/Drolban for metastatic breast cancer, exploiting its ability to compete with oestrogen at breast tissue — a genuine but dated clinical use, which anchors a modest research score. Modern use is cosmetic: it does not aromatise and produces no water retention, giving a dry, grainy appearance most noticeable in already-lean individuals.
Because it is a potent DHT derivative, its side-effect profile is androgenic — accelerated male-pattern hair loss in the predisposed, acne, and oily skin — rather than oestrogenic. It has a mild anti-oestrogenic action that can complement aromatising compounds. The propionate ester is short, so injections are typically every other day.
02 Mechanism
Androgen-receptor agonist derived from DHT; the 2-alpha-methyl group resists metabolism and it cannot aromatise, so it exerts androgenic and mild anti-oestrogenic effects without oestrogenic water retention.
03 Dosing
| Tier | Dose | Route | Notes |
|---|---|---|---|
| Common | 300–400 mg/wk | IM | Injected every other day due to short ester. |
| Heavy | 400–500 mg/wk | IM | Most effective in already-lean physiques. |
Ester comparison
| Ester | Half-life | Injection freq. | Testosterone by mass |
|---|
04 Effects
| Effect | Magnitude | Evidence | |
|---|---|---|---|
| Hardening / dry, defined lookReported to increase muscular definition and 'grain' at low body fat; a cosmetic effect not captured in clinical trials. | Anecdotal | ||
| Mild anti-oestrogenic effectHistorically used against oestrogen-sensitive breast cancer; can modestly blunt oestrogenic effects of other compounds. | Clinical | ||
| Preserved lean mass in a deficitPopular in cutting phases to retain muscle and fullness. | Anecdotal |
05 Side effects
| Effect | Severity | Frequency | Evidence | Countermeasures |
|---|---|---|---|---|
| Acne and oily skinAndrogenic stimulation of sebaceous glands. | Mild | Common | Observational | |
| Accelerated male-pattern hair lossAs a potent DHT derivative it can hasten scalp hair loss in genetically predisposed users. | Moderate | Common | Observational | |
| HPTA suppressionSuppresses endogenous testosterone production. | Severe | Universal | Observational |
06 Commonly used with
What drostanolone is combined with, and why. This is about intent rather than safety — the interactions table below covers what is dangerous. Nothing here is listed without what it costs.
| Compound | Frequency | Purpose & trade-off |
|---|---|---|
| Stacked compounds | ||
| Testosteronepropionate base | Masteron is almost always run on a testosterone base, whose matched short ester supplies the primary anabolic drive and keeps androgen levels physiological while Masteron adds hardening.Trade-off: Testosterone aromatises, so its estrogen and water retention can partly mask the dry look Masteron is being run for, often requiring an AI to manage. | |
| Trenbolone acetatecut stack | Paired in contest-prep and recomp cycles because Masteron's DHT-mediated hardening complements trenbolone's dry, dense muscle for a defined finish.Trade-off: Two strong androgens stack the sides — accelerated hair loss, oily skin and acne — and trenbolone adds its own neurological and cardiovascular burden. | |
| Support & ancillaries | ||
| AnastrozoleAI | Added to control estrogen from the aromatising testosterone base so the intended dry, hard aesthetic from Masteron is not blunted by water retention.Trade-off: Over-suppressing estradiol crashes libido, joint comfort and lipids, and Masteron's mild anti-estrogenic action can make it easy to push estrogen too low. | |
| Post-cycle | ||
| TamoxifenPCT | Used after the cycle to restart the HPTA suppressed by the testosterone base and Masteron by blocking estrogen negative feedback at the pituitary.Trade-off: SERM recovery is slow and imperfect, and tamoxifen commonly causes mood changes, visual disturbances and reduced IGF-1 during the PCT window. | |