i have been on levothyroxine for several years now and i used to be on a higher dosage but the doc lowered it significantly. i now feel like i am going to pass out or die from tiredness. it could be from other different pills im on, but i really only noticed it right after it was lowered. i do have several other conditions, even diabities that i take insullin for. i wonder if anyone else has had problems with the synthroid or levothyroxine?