Trenbolone enanthate, known by the nickname Trenabol, is a synthetic and injected anabolic–androgenic steroid (AAS) and a derivative of nandrolone which was never marketed.[1][2] It is the C17β enanthate ester and a long-acting prodrug of trenbolone.[1] Trenbolone enanthate was never approved for medical or veterinary use but is used in scientific research[3][4] and has been sold on the internet black market as a designer steroid for bodybuilders and athletes.[5][6]