I had Grave's Disease for several years that I eventually ended up choosing to go with the RAI treatment this past March. At that time, my TSH level was 0.025. Two months later, in MAY, my TSH level dropped even more to 0.004. Then all of a sudden, the whole month of June, I started to experience the worst feelings ever. I cried ALL the time, had major swelling in my face, hands, legs, feet, chest, mainly everywhere on my body, I had pitting edema. I gained 17 lbs in 2 weeks. So in June, the doc checked my TSH and it ended up being 76.91. He immediately started me on Synthroid 125mcg. The end of August my level FINALLY went to normal.... 3.3. The past 2 weeks I've been starting to feel quite crappy again. Had my level checked again and now it's at 17....doc upped my dose of Synthroid to 137mcg and I go back in 6 weeks to get checked again. My question, I guess, is when should I expect this RAI to STOP working? If I would have known the pure hell that this treatment was all about, I would have stayed with having Grave's.