As long as you don't have any thyroid dysfunction that is preventing the conversion of T4 to the active hormone T3, T4 will restore your T3 levels but it will lower your TSH in the process, obviously. It takes about 2 weeks on T4 before you start to feel better.

HOWEVER, anabolics like Tren that can lower T3 - upon cessation of the Tren your T3 levels should eventually return to normal on their own. If there is nothing wrong with your thyroid, the last thing on earth you want to do is start messing with thyroid hormones and possibly create a problem.

~~

BUT, If you are on cycle running Tren, you want to supplement with T3 directly if your LABS CONFIRM THAT YOUR T3 IS LOW. Most of the top sources on this website carry T3, you shouldn't need to resort to research chemicals. If u want my source, FR me.