Levothyroxine
"I was first treated with Levothyroxine for my hypothyroidism.  After 6 weeks of being on it, it had no effect whatsoever!  I asked my Doctor for Armour Thyroid, and boy what a difference!  It's great!  Too bad also that labs use an outdated reference range of what is "normal" on TSH, T-4, and T-3 blood levels.  Do your own research, because what the lab accepts as normal is not!"