Anavar is a synthetic steroid hormone that was first developed in the 1960’s by scientists at Sandoz Laboratories. It is a derivative of 17-alpha hydroxyprogesterone caproate (17OHP). Anavar is a progestin drug that works by binding to the same receptors as progesterone. It is commonly prescribed to treat endometriosis, breast cancer, uterine fibroids, benign prostatic hyperplasia (BPH), and acne. It is also used as a performance enhancer and muscle building supplement.