Methenolone Acetate (oral Primobolan)
The oral form of methenolone (Primobolan tablets). Unusually among orals it is not 17-alpha-alkylated, so it is far less hepatotoxic than typical oral steroids, but this also gives it poor oral bioavailability, requiring relatively large daily doses. It shares methenolone's mild, non-aromatising, DHT-derived profile: gentle lean gains with a low side-effect burden.
01 Overview
Methenolone acetate is the same active steroid as the injectable enanthate, formulated for oral use with a short acetate ester. Critically, it lacks the 17-alpha-alkyl group that makes most oral steroids liver-toxic; instead it relies on the 1-methyl group for some oral survivability, so hepatotoxicity is minimal but a substantial fraction is destroyed on first pass, making it inefficient and expensive to dose orally.
Its pharmacology is otherwise methenolone's: non-aromatising, low androgenicity, modest anabolic effect. Because oral dosing is inefficient, effective daily amounts are high, and the compound has a very short duration requiring divided doses. It remains suppressive and lowers HDL like other anabolic steroids despite its mild reputation.
02 Mechanism
Non-17-alpha-alkylated oral DHT derivative; moderate androgen-receptor agonist that cannot aromatise, with limited oral bioavailability and low hepatotoxicity.
03 Dosing
| Tier | Dose | Route | Notes |
|---|---|---|---|
| Common | 50–100 mg/day | Oral | Divided doses due to short duration and poor bioavailability. |
| Heavy | 100–150 mg/day | Oral | High daily amounts needed; cost is a limiting factor. |
Ester comparison
| Ester | Half-life | Injection freq. | Testosterone by mass |
|---|
04 Effects
| Effect | Magnitude | Evidence | |
|---|---|---|---|
| Mild lean muscle gainGentle lean gains with minimal water retention; modest in magnitude. | Anecdotal | ||
| Low hepatotoxicity for an oralLacking 17-alpha-alkylation, it spares the liver relative to most oral steroids. | Observational | ||
| Lean mass preservation while dietingUsed in cutting phases for muscle retention. | Anecdotal |
05 Side effects
| Effect | Severity | Frequency | Evidence | Countermeasures |
|---|---|---|---|---|
| Mild androgenic effectsAcne or hair-loss acceleration possible but low. | Mild | Uncommon | Observational | |
| HPTA suppressionSuppresses endogenous testosterone. | Moderate | Universal | Observational | |
| Adverse lipid changesOral anabolic steroids tend to depress HDL more markedly than injectables. | Moderate | Common | Observational |