Symptomatic Dermatographism- Huge Skin problem!?

I am 22, and had this problem since I was in high school in 11th grade. I would get up like 5 in the morning with a tingling feeling in my face, and feel a small ball swelling in my lower lip. A few minutes later it grew and swelled up more and it took up like almost my whole bottom lip. It was warm to the touch, and it did not itch at all, it just appeared. I used ice for the swelling and it took hours and sometimes half a day to go away and I had to miss a few days of school cause it was so embarring. I started crying and asking what is wrong with my mouth? I want my mouth back! It appeared on my lips, close to the nostril area on my nose, sometimes areas of my chin too. I saw an allergist, a dermitologist and they didn't find anything wrong. Family doctors said to take Allegra D-24 and have been taking it since then. It prevents it from happening at leaset. After high school, I had gone to Europe because my grandfather had soon died. After the funeral me and the family went to his second wifes house toretrieve some belongings he wanted us to have. I was in the car when we arrived, and then suddenly I had a brief itch on my neck, I scrathed, and then, the area I scratched, became swelled and looked like I had spagetti on my skin and I got scared. Soon after anywhere I scratched on me, the same thing appeared. I saw an Allergist there and she said the is was Symptomatic Dermatographism and gave me Allegra, or Xozal to take. It helped a little but we came back to the States and I still have it if I occasionally miss taking the Allegra. It's not as bad now, but it still bothers me. Is there a cure for this stuff? Or some way to get rid of it permenantly? How many years do I have to suffer from this. It's so embarring.