My 13 Year Old Has A Rash That Keeps Getting

My 13 year old has a rash that keeps getting worse. It started behind her ears and a bit on her chest. Now it has spread to her back, neck , more of her chest, up her hairline, and her ears are much worse - red and inflamed. The skin is very sensitive - her clothes can hurt if they rub against the rash. It is not particularly itchy. I have tried Claratin, Benadryl, Cort-Aid cream and even my prescription excema cream, Lidex. It started Monday and is getting worse?