Proviron is a synthetic steroid hormone used to treat hypogonadism. Bodybuilders and athletes have used it illicitly for performance enhancement.
Proviron is the brand name for the steroid hormone mesterolone, a testosterone derivative similar in structure to the naturally occurring hormone Dihydrotestosterone (DHT). As a steroid, Proviron causes strong androgenic (masculinising) and mild anabolic (tissue-building) effects.
According to Proviron's manufacturer, Bayer Pharmaceutical, doctors can prescribe Proviron to treat a deficiency of testosterone called hypogonadism. Proviron can alleviate or reverse the symptoms of hypogonadism, which may include low sperm production, lessened libido, a decrease of muscle mass and bone density and difficulty remembering or concentrating.
When used excessively, certain steroids can convert to oestrogen, and bodybuilders taking these steroids can suffer gynaecomastia (development of male breasts) as a result. Because Proviron blocks this conversion process, bodybuilders have used it to mediate the side effects of excess steroid use.
Because Proviron chemically resembles DHT, it exerts the same effects of increasing muscle hardness and promoting strength gains. For this reason, strength athletes have used Proviron to enhance performance in weightlifting, track and field, and other sports requiring strength and explosiveness.
As men age, their natural production of testosterone decreases. Doctors can prescribe Proviron as part of a regimen of hormone replacement therapy, and patients may experience increased libido and vitality, increased muscle mass and the alleviation of erectile dysfunction.
Men suffering from prostate cancer should not take Proviron as it can further enlarge or aggravate this gland. According to Drugs.com, steroids, even when taken for medical purposes, can elevate liver levels and cause changes to blood serum cholesterol, which can lead to arteriosclerosis, hypertension, stroke and congestive heart failure. Also, Bayer indicates that women should not take Proviron, as it can enhance masculine characteristics in both sexes, including excess facial and hair growth, acne, oily skin, deepened voice and male-pattern baldness.