I'm 16 years old and I was diagnosed with Hyperthyroidism (Graves' disease) in July. Since then, I have been on Tapazole (10 Mg, 3x/day). When I was first diagnosed, my T3 was 669; my T4 was 4.5 and my TSI was at 350. I was essentially asymptomatic. Now, my thyroid hormone levels are normal, but my TSI is slowly decreasing (it's 325 now). Lately, I've been having severe heartburn. I eat a snack when I come home from school and that's all. The heartburn occurs 2-3 hours after I have eaten. It lasts for about one hour. I don't take any pain relievers to ease the pain. I don't eat spicy food on a regular basis or red meat. I eat pretty well. I'm worried about this heartburn. I just want to know if this heartburn could be the result of thyroid disease. I should also mention that I have not been taking my medicine like I should. Lately, it's been once-a-day or not at all. And, if I'm lucky, twice-a-day.