In the most literal sense of the word, I am over-sensitive. I have a condition called dermatographism (or dermographism), which is a chronic urticaria condition not unlike my son's cold urticaria. With very little pressure, I can literally write on my skin, which means even the lightest scratches lead to welts, hives, or raised rashes. It's a little unnerving for massage therapists, I'm told, to see my skin react so strongly to their touch. Oh, and there's really no hiding a passionate makeout sesh over here...I'm left red-faced both literally and figuratively.
The above image is my arm, about thirty seconds after lightly using my nail to trace the shape of a heart on my skin. If I gently scratch, it leaves welts on the skin which last about twenty minutes to a half an hour.
Apparently it's a mast cell response, releasing histamines into the system, but it's not at all life-threatening, just generally unsightly. The resulting hives when the skin reacts aren't bothersome or itchy generally, but if I'm given a back scratch, the end result is pretty gruesome criss-cross welting like I've been whipped across my back.
And interestingly, although it's kind of like an allergic response, it's not an allergic response. It can definitely be exacerbated by an allergy, though. If I'm exposed to too much dust (oh, woe is me, dusting is legitimately harmful to my health!), the itching I do can causes major rashing and welting of my skin. And when nervous, the response is definitely heightened, too. A dose of antihistamines helps to clear it up, thankfully.
Only 4-5% of the population suffers from this condition, so I guess I kinda won the lottery, didn't I? And though my kids haven't shown signs of it yet, because it's often genetic, there's a good chance it's somehow linked to my daughter's eczema and my son's various allergies. Genetic sharesies, if you will. I'm such a giving parent, aren't I?
Want to read more? Here's what not to say to someone who has allergies.