SP-Laboratories PROVIRON



Package: 50 tabs (50mg/tab)

Active Substance: Mesterolone

Product Name: Proviron, Provimed, Mesterolone


Proviron, also known as Mesterolone, is a well-known oral drug manufactured by SP-Laboratories. It is a versatile medication with various applications, both in the medical field and in bodybuilding and sports. In this comprehensive guide, we will explore Proviron’s general description, indications, contraindications, uses in bodybuilding and sports, medical actions, combinations with other drugs, recommended dosages, and potential side effects.

General Description:

Proviron, the trade name for Mesterolone, is a synthetic androgenic and anabolic steroid (AAS). It was first developed in the 1930s and has been used for decades to treat various medical conditions. It is derived from dihydrotestosterone (DHT) and possesses unique properties that set it apart from other AAS.


Proviron has several medical indications, including:

  1. Hypogonadism: Proviron is used to treat male hypogonadism, a condition characterized by low testosterone levels. It helps to restore normal testosterone levels in men, improving libido, mood, and overall well-being.
  2. Infertility: In cases of male infertility caused by low sperm count or poor sperm motility, Proviron can be prescribed to enhance fertility.


While Proviron is generally safe when used under medical supervision, there are some contraindications and precautions to consider:

  1. Prostate Cancer: Proviron should not be used in individuals with prostate cancer or a history of prostate issues.
  2. Liver Dysfunction: People with liver diseases should use Proviron with caution, as it can affect liver function.

Uses in Bodybuilding and Sport:

Proviron has gained popularity in the bodybuilding and sports communities due to its unique properties. It is often used for the following purposes:

  1. Anti-Estrogenic Properties: Proviron is valued for its ability to reduce estrogen levels in the body. This makes it a useful addition to a steroid cycle, preventing estrogen-related side effects such as water retention and gynecomastia (breast tissue enlargement).
  2. Enhanced Muscle Hardness: Bodybuilders use Proviron to achieve a harder, more defined muscular appearance. It can enhance the look of muscles by reducing subcutaneous water retention.
  3. Increased Libido: Proviron can boost libido and sexual performance in athletes, which can be adversely affected by some other performance-enhancing drugs.

Medical Action:

Proviron exerts its effects through several mechanisms:

  1. Anti-Estrogenic: It inhibits the aromatase enzyme, reducing the conversion of testosterone to estrogen, leading to lower estrogen levels.
  2. Androgenic: Proviron has a mild androgenic effect, which can help improve male sexual characteristics.

Combining with Other Drugs

Proviron is often used in combination with other drugs in both medical and performance-enhancing contexts:

  1. In Medical Treatment: In medical settings, it can be combined with testosterone replacement therapy to enhance its effectiveness.
  2. In Bodybuilding: In bodybuilding, it is frequently stacked with other steroids to mitigate estrogenic side effects and enhance muscle definition.


The typical dosage of Proviron varies depending on the intended use:

  1. Medical Use: For hypogonadism or infertility, a common dose is 25-100mg per day, taken in divided doses.
  2. Bodybuilding: Bodybuilders often take 25-50mg per day, usually divided into two doses.

It’s important to note that Proviron should be used with caution and under the guidance of a medical professional.

Side Effects:

While Proviron is generally well-tolerated, it can still cause side effects in some individuals. Common side effects may include:

  1. Androgenic Effects: Acne, increased facial and body hair, and oily skin.
  2. Liver Issues: In rare cases, Proviron may lead to liver problems, especially when used at high doses or for extended periods.
  3. Mood Changes: Mood swings and irritability are possible side effects.


Proviron (Mesterolone) by SP-Laboratories is a versatile medication with applications in medical treatments and the world of bodybuilding and sports. It offers unique anti-estrogenic properties, making it a valuable addition to various treatment regimens. However, it should always be used responsibly and under the supervision of a healthcare professional to minimize the risk of side effects and ensure safe and effective use.