Hi

I've suffered from urticaria for about 10 years although I'm pretty sure mine is from hormonal or emotional origin rather than an external source.  If you google "dermographic urticaria" then that might answer some questions.

One very helpful thing I have found is that plain cornflour for some reason calms the itching.  Just dip your finger in a pot and smooth it over the itchy bits.  Apparently making a cream with white or cider vinegar is even better and if anyone can find a way of handling the resulting stuff I'd like to hear it!  I just use it neat.

 Sue