Can anyone help me I have been having palpitations and racing heart for most of the time I have been on thyroxine which is now 35years. I have now been diagnosed with having atrial fibrillation. I was so ill a couple of weeks ago that I had to go to A and E. I was seen by a lovely doctor he was so kind and caring I couldnt believe it. He took my blood and demanded they get the results there and then even though it was nearly midnight. We then had quite a long talk about my thyroid problem and the fact I had RAI in 1982 and have been on thyroxine ever since. He said I was awash with hormone and that it was possible that some thyroid tissue had regenerated, I was shocked at that , dont know if anyone has heard of thyroid tissue regenerating They are actually doing tests at the moment to find out. Straight away they reduced my dose of thyroid hormone from 100mcg to 50mcg and I am beginning to feel the effect, low energy, achy throat, hoarse voice, I am not looking forward to the future at the moment. What I would like to know has anyone had this problem as well as thyroid issues and how did they cope with it, I would appreciate any advice, supplements, medication etc. Where do I go from here???