Description

Proviron (Mesterolone) 25 mg x 20 pills per package

Proviron, the brand name for mesterolone, is a synthetic type of male sex hormone. Mesterolone, chemically known as 1-methyl-5?-dihydrotestosterone (DHT), is methylated (the addition of a methyl group –CH3) making it an active steroid very similar to natural DHT that does not convert into estrogen or progesterone (both female hormones) once in the body. Proviron has many positive effects on the body, including increasing muscle mass, enhancing testosterone levels and treating male sexual dysfunction.

Testosterone Enhancer
Proviron on its own is considered to be a weak steroid according to a study by A.T. Kicman published in the British Journal of Pharmacology. However, it has unique properties that make it a useful and effective enhancer, especially of testosterone. In normal levels in the body, testosterone is mostly inactive because most of it is bound by sex hormone binding globulin (SHBG) and albumin. Proviron also has a great affinity for SHBG, so when administered, it will bind to the SHBG, leaving more testosterone free.

Proviron (Mesterolone) 25 mg x 20 pills per package

Like other AAS, mesterolone is an agonist of the androgen receptor (AR).^[1] It is not a substrate for 5α-reductase, as it is already 5α-reduced, and hence is not potentiated in so-called “androgenic” tissues such as the skin, hair follicles, and prostate gland.^[1] Mesterolone is described as a very poor anabolic agent due to inactivation by 3α-hydroxysteroid dehydrogenase (3α-HSD) in skeletal muscle tissue, similarly to DHT and mestanolone (17α-methyl-DHT).^[1] In contrast, testosterone is a very poor substrate for 3α-HSD, and so is not similarly inactivated in skeletal muscle.^[1] Because of its lack of potentiation by 5α-reductase in “androgenic” tissues and its inactivation by 3α-HSD in skeletal muscle, mesterolone is relatively low in both its androgenic potency and its anabolic potency.^[1] However, it does still show a greater ratio of anabolic activity to androgenic activity relative to testosterone.^[1]

Mesterolone is not a substrate for aromatase, and so cannot be converted into an estrogen.^[1] As such, it has no propensity for producing estrogenic side effects such as gynecomastia and fluid retention.^[1] It also has no progestogenic activity.^[1]

Because mesterolone is not 17α-alkylated, it has little or no potential for hepatotoxicity.^[1] However, its risk of deleterious effects on the cardiovascular system is comparable to that of several other oral AAS.^[1]