Hello, I went to the doctor on Monday (17-11-14) after months of being tired, cold and just feeling plain off. He sent me off for blood work, and I saw him again on Wednesday (19-11-14). At this visit he told me I had anemia and needed to take an iron supplement. I was prescribed with Iron Ferrous Sulfate 300 mg (60mg iron). I took my first tablet right away on Wednesday, which means I just took my third. Within the hour of taking it today my throat started to feel really tight like I can not breathe. I am really worried. I hope it will pass, but is this a reaction to the iron, or another underlying condition?