With category 2 Trenbolone side effects in mind this is the reason it is always best to stick with short or small ester based Tren such as Trenbolone-Acetate. If the negative reactions become too strong if you are using a small ester Tren form you can simply discontinue use and your system will be clear of the hormone in a matter of a 2 maybe 3 days. However, if you’re supplementing with large ester forms such as Trenbolone-Enanthate and problems arise you can still discontinue use but you’re going to be dealing with the problems for as long as 2-3 weeks as it will take this much time for the steroid to begin to clear.
Some bodybuilders and athletes use trenbolone for its muscle-building and otherwise performance-enhancing effects. [ citation needed ] Such use is illegal in the United States and many other countries. The DEA classifies trenbolone as a Schedule III controlled substance 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 .  The infamous "duchess" cocktail administered to Russian athletes at the Sochi Winter Olympics consisted of oxandrolone , metenolone , and trenbolone. 
Stephan Bonnar and Josh Barnett , mixed martial arts (MMA) fighters from the UFC and PRIDE Fighting Championships , have also tested positive for the banned substance.  After the World Extreme Cagefighting show on January 20, 2006 Muay Thai turned MMA fighter Kit Cope also tested positive for boldenone.  Following the Strikeforce card on June 22, 2007 former PRIDE and UFC fighter Phil Baroni tested positive for boldenone, as well as stanozolol .  At a K-1 WGP event in Las Vegas on August 17, 2007 two fighters, Rickard Nordstrand and Zabit Samedov , both tested positive for boldenone.  Alexandre Franca Nogueira tested positive for boldenone in July 2008.