Some bodybuilders and athletes use trenbolone esters for their muscle-building and otherwise performance-enhancing effects.  Such use is illegal in the United States and many other countries. The DEA classifies trenbolone and its esters as Schedule III controlled substances under the Controlled Substances Act .  Trenbolone is classified as a Schedule 4 drug in Canada  and a class C drug with no penalty for personal use or possession in the United Kingdom .  Use or possession of steroids without a prescription is a crime in Australia . 
Non-medical users of anabolic steroids often “stack” different anabolic steroids over the course of a “cycle” of use. They also administer various ancillary drugs and substances to enhance the desired effects of anabolic steroids or to minimize adverse side effects. The most common liquid (injectable) anabolic steroids encountered in these cases are (oil-based) esters of testosterone (., testosterone cypionate, testosterone enanthate, and testosterone propionate, and a blend of testosterone esters called Sustanon 250) or nandrolone (., nandrolone decanoate). Also popular are Equipoise (boldenone undecylenate) and trenbolone acetate and trenbolone enanthate, as well as the water-based injectable Winstrol (stanozolol). Popular oral anabolic steroids include methandrostenolone (Dianbol), oxandrolone (Anavar) and oxymetholone (Anadrol 50).