Hi Brian!
Well, as I said, I was diagnosed with dermatographism about 10 years ago. I haven't found that it gets any better - at least it hasn't for me. I've read that some people may only have it for a few weeks/months/years and then it clears up by itself. Unfortunately that wasn't the case for me.

As for what triggered it: I've always been very bad about getting infections - sinus infections, tonsilitis, strep throat, bronchitis, pneumonia, ear infections, etc. Ear infections are the wors - seems like I have one constantly! Well, I was in the fourth grade, just getting over a bout of bronchitis with an ear infection when I went outside in some tall grass by my house to play. The grass made me all itchy, so I started scratching my legs - next thing you know, my legs were covered in long red whelts. This went on for several weeks - scratch, swell up, scratch more, swell more. Finally I went to my doctor and he said that I had dermatographism and that it was probably caused by my recent ear infection. How he figured that, I don't know! Since then, it's seemed that instead of just getting an itch and scratching and swelling up, I itch all over, all the time now. I've pretty much tried everything I can think of to be rid of this stuff - at least the itching - and nothing's helped. Now I just try to bear it and scratch as little as I can!
It's great that you're going to the doctor! He/she will probably put you on an allergy pill like Zyrtec or something - whatever the doc tells you to try, try it! SOme of those meds work for some people, so it doesn't hurt to try! Let me know if the doc puts you on any meds, and let me know if they help!
Good luck!!
Amanda