Mesterolone

Mersterolone (1-methyl dihydrotestosterone) is an oral-androgen, which is mainly used to avoid side effects of anabolic steroids. Mostly it is manufactured by Bayer under the brand name Proviron. Proviron is a potent androgen with a weak level of anabolic activity. Mesterolone rapidly inactivates the diol metabolites in muscle tissue where the levels of 3-hydroxysteroid dehydrogenase enzyme are high. The belief that the weak anabolic nature of this compound indicates a tendency to block the androgen receptor in muscle tissue, thereby reducing the gains of other more potent muscle-building steroids, should likewise not be taken seriously. ln fact, due to its very high affinity for plasma binding proteins such as SHBG, Proviron may actually work to potentate the activity of other steroids by displacing a higher percentage into a free, unbound state. Among athletes, mesterolone is primarily used to increase androgen Ieveis when dieting or preparing for a contest, and as an antiestrogen due to its intrinsic ability to antagonize the aromatase
enzyme.