Masteron (Drostanolone) Explained: Science, Uses, and Risks in Bodybuilding (2025)

Reviewed and authored by Dr. Aaron Blake, PhD, CSCS Exercise Physiologist & Sports Nutrition Researcher – Educational Content Only

What Is Masteron?

Masteron, also known by its chemical name Drostanolone, is an anabolic-androgenic steroid (AAS) originally developed in the 1950s. It was first marketed under brand names such as Masteron or Drolban and prescribed for the treatment of breast cancer in women due to its anti-estrogenic properties.

Although it is no longer widely used medically, Masteron remains a subject of interest in sports science because of its unique androgenic structure and impact on muscle composition under laboratory and athletic study conditions.

Masteron or Masterone – Same Compound, Different Spelling

Both Masteron and Masterone refer to the same steroid: Drostanolone. The variation in spelling comes from branding differences among manufacturers, but chemically, they are identical.

Masteron Steroid for Sports and Bodybuilding

In modern sports culture, Masteron steroid is often discussed for its role in physique preparation — particularly during cutting phases when athletes aim to reduce body fat while maintaining lean muscle mass.

It is considered by many athletes to promote a “hardening” or more defined look, partly because of its low water-retention profile and anti-estrogenic effects. However, its use for physique enhancement is banned by the World Anti-Doping Agency (WADA) and carries significant health and legal risks.

What Does Masteron Do? (Mechanism Overview)

Masteron is derived from Dihydrotestosterone (DHT) — a potent androgen. Its main actions include:

• Binding strongly to androgen receptors, influencing protein synthesis.
• Reducing estrogenic activity through weak anti-estrogenic properties.
• Improving nitrogen retention, aiding in muscle preservation during caloric deficits.
• Decreasing subcutaneous water, creating a leaner, more defined appearance.

Because it is non-aromatizing (it doesn’t convert to estrogen), Masteron was historically used alongside other steroids to balance estrogenic side effects in certain regimens.

Medical and Research Background

Originally, drostanolone propionate was used medically to inhibit estrogen-reliant breast cancer. Its androgenic properties made it less favorable for long-term clinical use, and safer alternatives later replaced it.

Today, research references mainly focus on its endocrine effects, androgen receptor activity, and impact on muscle tissue physiology under controlled study conditions.

Masteron Esters: Propionate vs Enanthate

Form	Half-Life	Common Discussion Context	Notes
Masteron Propionate	2–3 days	Shorter-acting; used more frequently in cycles	Historically the original form
Masteron Enanthate	7–10 days	Longer-acting; requires fewer injections	Modern adaptation; similar effect profile

Both are drostanolone esters, differing mainly in release rate and injection frequency. Their physiological effect once active is largely the same.

Does Masteron Lower Estrogen?

Yes, indirectly.
Masteron shows mild anti-estrogenic behavior, meaning it can inhibit estrogenic side effects (like water retention or gynecomastia) when combined with aromatizing steroids. However, it is not an aromatase inhibitor and cannot fully replace medications like anastrozole in clinical use.

In other words, it helps limit estrogenic symptoms, but does not block estrogen production completely.

Does Masteron Increase Libido?

Some users report temporary increases in libido due to higher androgen activity. However, prolonged exposure to exogenous androgens like Masteron can suppress natural testosterone production, leading to the opposite effect once discontinued. Therefore, the libido response is inconsistent and depends on baseline hormonal balance and post-cycle recovery.

Can Masteron Cause Erectile Dysfunction?

Yes, indirectly. While it may initially enhance libido, Masteron can suppress natural testosterone over time. Once endogenous testosterone declines, erectile dysfunction (ED), fatigue, and low mood can occur.
These effects are reversible with medical supervision, but unsupervised use increases long-term risk of hormonal dysfunction.

How Long Does Masteron Stay in the System?

• Masteron Propionate: 2–3 days half-life
• Masteron Enanthate: 7–10 days half-life

Complete clearance can take up to 2–3 weeks depending on ester type, metabolism, and frequency of administration. Doping tests can detect metabolites for up to several months, which is why it is strictly prohibited in competitive sports.

Masteron with TRT (Testosterone Replacement Therapy)

In theory, some individuals discuss Masteron with TRT for its potential to maintain lean definition and control estrogen.
However, medical TRT programs do not include Masteron because:

• It is not approved for testosterone deficiency treatment.
• It can exacerbate lipid imbalance and lower HDL cholesterol.
• It suppresses rather than supports natural testosterone when misused.

Clinical endocrinology prefers regulated testosterone esters with known dosing and safety data.

Drostanolone vs Masteron – Are They the Same?

Yes.
Drostanolone is the chemical name, while Masteron is the brand name historically used by pharmaceutical companies. They represent the same compound, drostanolone propionate or enanthate, depending on formulation.

Primo or Masteron with TRT – Scientific Comparison

Compound	Base Hormone	Aromatization	Typical Discussion Context
Primobolan (Methenolone)	DHT-derived	None	Often discussed for lean mass preservation
Masteron (Drostanolone)	DHT-derived	None	Discussed for muscle hardening and anti-estrogenic effect

Both are DHT derivatives, but Primobolan is considered milder, whereas Masteron is stronger and more androgenic.
Neither compound is approved for TRT or hormone therapy use outside research.

Equipoise vs Masteron – Key Differences

Feature	Equipoise (Boldenone)	Masteron (Drostanolone)
Chemical origin	Testosterone derivative	DHT derivative
Aromatization	Moderate	None
Water retention	Mild	Minimal
Muscle appearance	Fuller, more volume	Harder, leaner
Half-life	Long (14 days)	Short (2–10 days)

Equipoise is typically linked to slow, steady mass gain, whereas Masteron is linked to hardness and definition — again, within research and athletic discussion, not clinical application.

Masteron Side Effects (Health & Endocrine Risks)

Like all anabolic steroids, Masteron carries potential for serious adverse effects:

• Hormonal suppression (low natural testosterone, infertility risk)
• Lipid profile disruption (lower HDL, higher LDL)
• Liver strain (especially with oral compounds)
• Hair loss or acne (due to DHT conversion)
• Mood and sleep changes
• Cardiovascular strain (elevated BP, cholesterol imbalance)

Prolonged unsupervised use may increase heart, kidney, and endocrine risk, especially in individuals with pre-existing conditions.

Masteron for Sale / Buy Masteron Online – Legal Status

Masteron is a controlled substance under U.S. federal law (Schedule III) and Australian law (Schedule 4/Anabolic category).
It is illegal to purchase or sell for personal use without prescription. Online sales claiming “Masteron for sale” or “buy Masteron online” are unregulated and unsafe, with high risk of counterfeit or contaminated products.

Masteron Reddit Discussions – Why They Trend

On platforms like Reddit, discussions about Masteron often focus on cutting cycles, visual appearance, and personal anecdotes. While these forums can offer peer insights, they lack scientific verification and should not replace professional medical advice or clinical data.

Key Takeaways: Masteron in 2025 Research & Athletic Context

• What it is: A DHT-derived anabolic steroid (Drostanolone).
• Why it’s used in bodybuilding: Promotes a lean, dry, “hard” muscle appearance.
• Medical status: Discontinued for therapeutic use; not approved for physique or TRT.
• Health risk: Hormonal suppression, lipid imbalance, cardiovascular strain.
• Legal status: Controlled substance in most countries.