Drostanolone Propionate is an anabolic androgenic steroid that first hit the market around 1970 under the trade name Masteron manufactured by Syntex. Drostanolone Propionate is a dihydrotestosterone (DHT) derived anabolic steroid. Specifically, Masteron is the DHT hormone that has been structurally altered by the addition of a methyl group at the carbon 2 position, This protects the hormone from the metabolic breakdown by the 3-hydroxysteroid dehydrogenase enzyme, which is found in the skeletal muscle. It also greatly increases the hormone’s anabolic nature. This simple structural change is all it takes to create Drostanolone, and from here the small/short Propionate ester is attached in order to control the hormone’s release time. On a functional basis, Masteron is well-known for being one of the only anabolic steroids with strong anti-estrogenic properties. Not only does this steroid carry no estrogenic activity, but it can actually act as an anti-estrogen in the body. This is why it has been effective in the treatment of breast cancer. In fact, the combination of Masteron and Tamoxifen Citrate has been shown to be far more effective than chemotherapy in the treatment of inoperable breast cancer in postmenopausal women. This also makes it a popular steroid among bodybuilders as it could actually prohibit the need for an anti-estrogen when used in the right cycle.