Well the Claritin kicked in around 11 pm and the rash is almost gone. Now the Claritin is making me sleepy. (Everything makes me sleepy. A doctor once told me I'd never make it as a drug addict.)

I'm still not gonna eat any blueberries tomorrow. I guess it's time to find an allergist. The last time I went to an allergist was after the mystery hives, and she did some tests and told me I wasn't allergic to anything. I didn't like her. But I work with a guy who has all kinds of hayfever problems, so maybe he can recommend someone good (who accepts our insurance).

I never felt any signs of airway constriction. In fact to distract myself from the itching, I measured my sit bones earlier. I put my yoga mat on my dining room table (which has a marble top), folded the mat a few times, and sat on it while I played several rounds of a word game on my phone to kill time. That gave me good indentations that lasted long enough for me to measure. I came out with ~140 mm from outside to outside and ~120 center to center. Which means either the Bontrager measuring thing at the LBS is totally whack or I wasn't making good contact with my sit bones when I sat on it last weekend (it told me I wanted a 140 mm saddle).

BTW, this sounds very much like what happened, although it doesn't explain why the histamines went so crazy:

Dermatographia. The name of this condition literally means "write on the skin." When pressure is applied to the skin or the skin is scratched, raised lines appear on those areas due to histamine-based angioedema that leads to swelling beneath the skin.

I found it on mayoclinic.com:

http://www.mayoclinic.com/health/hiv...SECTION=causes

So that's something for me to google to see if I can learn more. But I'll do that tomorrow.

Thanks everyone!