I was diagnosed before Christmas with Fibromyalgia. I also have hashimoto's thyroiditis confirmed with a fine needle aspiration on my thyroid. I have had hashimoto's for 7 years. Anyway, back in Ocotober I had sinus congestion and vertigo. It was a holiday so the DR. concerned that it might be an infection called in a script for me, augmentin and told me to take zyrtec. One week later to the day I broke out in hives all over my body, head to toe, long story short it took cortisone shot, steroids, and zyrtec to clear me up. After 4- 5 days it was MUCH better, but for a few weeks after that I would still ge tthem here and there, nothing major. The Dr. eventually tested me for penicillin allergy through rast testing and it came back negative. Although from what i have read rast really is not a very sensitive test and therer can be false negatives.Along with the hives my neck was sore,and my face would get itchy and numb. Just wondered I guess if with fibro. people had more drug allergies or can have just one case of acute hives for no reason. Anyone with anything like this I would welcome info!!