Hello, There are a number of things we can do to treat dermographism, but the sore throat concerns me and I would like to refer you to a gastrointerologist for an upper g.i, but the referral will have to come through your primary doctor. Here are suggestions: You asked about diet. I came across a histimine diet and it is my files, have never had to use it, but if this is something you are interested in I would have to be able to attach it. I think this may be possible through the paid question scenario. I will check on this. Are you taking an oral antihistimine?; H2 - receptor antagonists like Cimetidine? Cimetidine might help your sore throat if caused by acid reflux, someone needs to examine your throat. No hot baths or showers. Warm or slightly cool only. Cromoglycate ointment rubbed all over your body helps the itching and lesions. Acupuncture has had great success treating this illness and you might benefit greatly from trying this intervention. Thank you for coming to HCM and chatting with me. I wish you the best. Kathryn Shattler, MS,RDN