16 years ago I started getting welts on my skin, at first it was only if I was near something scratchy or was rubbed across my skin. As time went on I would latterly take off my shirt after work (I was a production baker) and it looked like I was attacked by a whip. My skin would have large welts and would take anywhere from 10 minutes to an hour to calm down and not look so angry.
As a baker I would use lots of different kinds of ingredients. One ingredient was to make a donut called a cruller, some might know this product. You measure say 2 cups of mix and off set with 4 cups of eggs (yea you heard me 4 cups of eggs). Personally I think there nasty; when you bite into the donut you get a blast of egg air. One day to save money the mix had dried egg added to replace using fresh eggs, not long after is when I started getting the skin welts and very itchy. I figured ok maybe this mix is why I am having this issue, an allergic reaction.
I ended up leaving that job to move into the technical field but, the symptoms never left. My Doctor feels the new cruller mix may have just been the catalyst to start my condition.
I now have dermographia in my life and have had for 16 years now. I spent at least 5 of those years in pure agony, sweating, wrong material, shower to hot or cold. Even a simple hair cut would have the hair dresser freaking thinking she did something wrong as my neck welted up. (My Wife does my hair now). My Doctor had never heard of the condition, so between his books, me on Google search we found the name, what causes and what can help with the welts. Wikipedia has information on what dermographia is and what causes it.
It turns out taking antihistamines helps to curve the welts or hives. If I become overly upset or depressed, red rashes will appear on my forehead, basically people at work see me as a walking mood ring. I take 1 extra strength reactine each night before bed, this helps control the welts and itching.
It did come in handy once, it was about 10 years ago before I found out about using antihistamines. I was at a technical convention here in Ontario, the young lady behind the table ran out of name tags. Being nonchalant I reached over and picked up her letter opener, placed it on my forearm (I think she thought I was about to lose my shit and start digging). I wrote my name lightly on my arm and tada I now had my name on a skin tag! That sucker welted up like a bright red flame. The lady would not look me in the eye after that.
Sadly there is no cure for dermographia, some people have it forever and others wake up one day and it is gone. I would to wake up and see it gone but alas it is there every morning waiting to say hello. Some people have learned to make Skin Art with it, me I cannot bring myself to do it as it drives me spinney being so itchy.