I will weigh in a little here on t3 because Ive been on it medically once, and am currently using it off label now (three days in)
theres a lot of scarey info about t3, and it should ALL be headed, also if you dont understand how your pituitary works in relation to your thyroid and how thyroid stimulating hormones works with t4 to t3 conversion...how this entire process works...please don't play with it.
read up, a LOT
also, what I find interesting is, dr's are prescribing it for fibromyalgia and depression and extreme fatigue issues.
I feel fine and m back to normal energy levels on it, but I have a history of thyroid cancer so the dr likes to see really low tsh numbers on me anyway and I feel good on those numbers.
Really research it, being someone that suffers from thyroid issues is no fun, don't accidentally create issues. You cant even imagine how dramatically your body can be potentially affected.