Christine
I had a problem with hives. I got them every day starting at about 4:00 p.m. I also went to a dermotologist and many of the same tests you had. We did not come up with anything either. He finally told me to take 1 or 2 benedryl (the pink/white/purple capsules) every night before bed. Having the antihistime in my system seemed to keep them at bay. I stopped when I became pregnant and so did the hives. I had my baby 3 months ago and started back to work 1 month ago. I have gotten hives 2 times since returning to work, but not too bad. I really think for me, it is stress. I started getting the hives 1 month after my Mom was diagnosed with lung cancer. She died within a year, although I continued to take the Benedryl for 5 months after until I finally got pregnant. Do you have lots of stress?