Estrogenic Activity: Low
Liver Toxicity: Low
Half Life: 12-13 hours
Drug Class: Androgen; Anabolic steroid
Bioavailability (oral): 3%
Dosage: 25-75mg for 4-10 weeks
Mesterolone, sold under the brand name Proviron among others, is an androgen and anabolic steroid medication which is used mainly in the treatment of low testosterone levels. It has also been used to treat male infertility, although this use is controversial. Mesterolone has been introduced as a highly effective oral androgen which can stimulate spermatogenesis without suppressing the pituitary. Despite its long track record of safety and efficacy, Mesterolone has never been approved by the FDA for sale in the United States.
Bodybuilders and athletes particularly like the low estrogenic side effects of Mesterolone and often use it in the cutting phase of their transition. When used in conjunction with other compounds Mesterolone has shown to make other compounds more effective by releasing them from the SHBG into a free state. It has proven to effectively adjust the androgen to estrogen level, creating a desirable hardness and density to ones physique.