Hi, I'm usually on the Fibromyalgia forum, but am having a heck of a time with my thyroid. I was already losing weight when they found (accidentally) in Sept. that my thyroid was underactive. The dr. started me out at 100 mcg. of levothyroxine. Since then I've lost even more. Twice now (in the last few months) they've lowered the dosage. Now I'm taking 50 mcg. I really don't want to keep losing! Should I have tests other than the TSH?