urticaria
"I suffer from Giant Urticaria which is caused from several different things like Pepsi Max and Persil Washing Powder. 

My Dr. provided 10mg Cetirizine and I take it only when the reaction starts and within 30 minutes the itchiness stops and after a few hours the hives and redness have completely gone. It does make me very drowsy but that's a small price to pay for relief. Great product, highly recommended."