Etiocholanolone is a steroid hormone that is produced by the liver from testosterone. It is often referred to as the "diol" form of testosterone due to its molecular structure. However, there are several other synonyms for etiocholanolone, including androstanolone, 5α-androstan-3α-ol-17-one, and 3α-hydroxy-5α-androstan-17-one. Etiocholanolone is commonly used in sporting drug testing as an indicator of anabolic steroid use due to its presence in the urine of athletes who have taken steroids. While it is a natural hormone, high levels of etiocholanolone can lead to health issues such as acne, hair loss, and changes in mood and behavior.