Eczema/Dermatitis?

Im going to go see a dermatologist and allergist very soon.  Just wondering what types of questions I should be asking.  I experience chronic burning in my legs that vary in moderations, but are usually around 4-5/10.  I don't feel it so much in my legs right now and it seems to have traveled up to the sides of my lower stomach.  This is very weird and unpleasant and im using antihistamines and creams to alleviate the sensations to a lower degree.  Does this last forever?  I had this chronic feeling for nearly two years and it just went away for more than 5 months, but now its back.  The only difference in living was sex both times that I noticed this unpleasantry after.  Any advice is most appreciated