Mesterolone (Proviron)

What is Mesterolone (Proviron)?

Mesterolone, most commonly known by its brand name Proviron, is an oral androgen and anabolic steroid (AAS). It is a synthetic derivative of dihydrotestosterone (DHT).

Other names:

• Proviron

• 1α-Methyl-DHT

• 1α-Methyl-4,5α-dihydrotestosterone

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Benefits and Uses

Medical Benefits:

• Androgen Deficiency: Mesterolone is primarily used to treat low testosterone levels (hypogonadism) in men. It helps to restore normal androgen levels and alleviate symptoms like fatigue, low libido, and decreased muscle strength.

• Male Infertility: It is also used to treat male infertility, particularly in cases of oligospermia (low sperm count), as it can increase sperm count and improve sperm quality.

• Lack of Estrogenic Effects: A significant benefit of Mesterolone is that it does not aromatize (convert to estrogen). This means it does not cause estrogen-related side effects like gynecomastia (male breast tissue development) or water retention.

Potential Performance-Enhancing Benefits (non-medical):

• Increasing "Free" Testosterone: Mesterolone has a high affinity for sex hormone-binding globulin (SHBG). By binding to SHBG, it can increase the amount of "free" testosterone in the body, which is the biologically active form of the hormone. This can enhance the effects of other steroids when used in a cycle.

• Hardening and Definition: Due to its strong androgenic and weak anabolic properties, it is often used by bodybuilders to achieve a harder, more defined look without adding significant muscle mass or water weight.

• Anti-Estrogen Properties: Its inability to convert to estrogen and its potential to act as an anti-estrogen make it useful for counteracting the estrogenic side effects of other anabolic steroids.

Side Effects and Risks

Mesterolone, like all androgens and anabolic steroids, has potential side effects. These are typically dose-dependent and can include:

Androgenic Side Effects:

• Acne and Oily Skin: Increased androgenic activity can stimulate sebaceous glands, leading to acne.

• Hair Loss: In individuals predisposed to male pattern baldness, Mesterolone can accelerate hair loss due to its DHT-like properties.

• Increased Body Hair: Users may experience increased body hair growth.

• Prostate Enlargement: DHT can stimulate prostate tissue growth, which may lead to benign prostatic hyperplasia (BPH) or other urinary symptoms.

Cardiovascular Side Effects:

• Altered Cholesterol Levels: Mesterolone can negatively impact cardiovascular health by decreasing high-density lipoprotein (HDL, "good" cholesterol) and increasing low-density lipoprotein (LDL, "bad" cholesterol).

Other Side Effects:

• Suppression of Natural Testosterone: While less suppressive than many other steroids, long-term or high-dose use can lead to suppression of natural testosterone production.

• Psychological Effects: Some users report mood swings, increased aggression, or irritability.

• Liver Toxicity: While often considered "liver-friendly," there is still a risk of hepatotoxicity, and liver function should be monitored.

• Priapism: Frequent or prolonged erections can occur.

Pros and Cons

Pros:

• Does not aromatize into estrogen, preventing gynecomastia and water retention.

• Can increase "free" testosterone by binding to SHBG.

• Adds muscle hardness and definition.

• Generally considered to be well-tolerated by the liver at therapeutic doses.

• Effective for treating specific medical conditions like hypogonadism and male infertility.

Cons:

• Strong androgenic side effects, including hair loss and acne.

• Can negatively impact cardiovascular health by altering cholesterol levels.

• May suppress natural testosterone production.

• Relatively weak anabolic effects, making it less effective for significant muscle mass gains compared to other steroids.

• Potential for prostate enlargement.

Dosage and Frequency

Medical Doses:

• For androgen deficiency or declining physical activity: 25 mg three times daily, followed by a maintenance dose of 25 mg once or twice daily.

• For hypogonadism: 25-50 mg three to four times daily for several months.

• For male infertility: 25 mg two or three times daily for a period of about 90 days.

Non-Medical Doses:

• Dosages used for performance enhancement can be higher, with some users taking up to 150 mg per day. However, such dosages are not medically recommended and increase the risk of side effects.

Half-Life and Detection Time

• Half-life: The elimination half-life of Mesterolone is approximately 12-13 hours.

• Detection Time: The detection time can vary depending on the specific drug testing methods used. Mesterolone can be detected in urine for up to several weeks (approximately 9-12 days or longer) after the last dose due to the presence of long-term metabolites.

Sterogenic, Progestogenic, and Prolactin Effects

• Estrogenic: Mesterolone is not estrogenic. It does not convert to estrogen, which is a key characteristic that prevents common estrogen-related side effects. In fact, it has anti-estrogenic properties.

• Progestogenic: Mesterolone is not a progestin and has no progestogenic activity.

• Prolactin: Mesterolone is not known to directly increase prolactin levels. It can even help to lower high prolactin levels caused by some other steroids.

Anabolic-Androgenic Ratio

The anabolic-androgenic ratio is a way to measure a steroid's relative anabolic (muscle-building) and androgenic (masculinizing) effects. The ratio is typically compared to testosterone, which has a ratio of 100:100.

Mesterolone is known for its strong androgenic effects and weak anabolic effects. Its anabolic-androgenic ratio is approximately 30-40:150. This highlights its role as a compound that primarily promotes male characteristics (androgenic) rather than muscle growth (anabolic).