I've had hyperthyroidism for over 13 years. They first diagnosed me with Graves Disease which was treated with Tapozole but later they changed the diagnosis to Hashimotos Thyroditis since I had a high thyroid antibody blood test and would also swing to low thyroid occasionally. I can definitely attest to the fact that an overactive thyroid is much worse than an underactive one having both. I, too, had many of the same symptoms listed above. The heart palpitations and skipped heartbeats would literally drive me crazy. After suffering with major digestive problems since last year, I at first thought it was thyroid related since I was losing so much weight and having constant diarrhea. All of my thyroid tests came back normal, so I began to research other areas. I am now convinced that I am mercury toxic since I have over a dozen fillings for over 35 years. I now have read that autoimmune thyroid disease is directly connected to mercury toxicity. I am almost through removing my fillings and am hoping that not only will my digestive problems be gone but also my thyroid problems. The above post makes me even more hopeful!