Help ASAP - eczema or allergies? need solution

[ctstuve]

My 3 year old son has been getting rashes and itches really bad on his back and stomach. But the catch is it's only in the winter months. Occasionally he will get itchy in the summer, but it's extremely bad in the winter. So bad that it often keeps him and me up at night. He has sensitive skin, so all I can use on him in the bath is a bar of Ivory soap for his hair and body. I've tried mild lotions to help keep his skin moisturized but everything I've tried so far, he's been allergic to. Is this extremely dry skin or an allergy to something else being used. The thing that has me stumped is that it only happens in the winter. I give him Benadryl Allergy medicine to help relieve the itching and I rub extra virgin olive oil on his skin to help moisturize, but it still doesn't seem to help. I'm not sure if he's allergic to the allergy medicine or if it's dry skin or an allergy to something completely different. But why the change between summer and winter months? I've taken him to our family doctor several times and all he can give me is cortizone cream and tell me to find something mild to moisturize his skin with. Not much help. I'm at my whits end because I don't know how to help him and I feel so useless and bad for him. I want to find out what the problem is but I don't know where to begin. Anyone out there ever heard of this before? When he was a baby he had really bad eczema on his cheeks. I don't believe it was only in the winter months though. He grew out of that and then started this real bad itching on his back and stomach. I tried Eucerin brand Aquaphor on him the other night. I tried a tiny spot on his back. The next morning there was no rash in that spot, so I tried another spot on his back. No rash. The next day I tried the inside of his arm. No rash. So that night I rubbed the Aquaphor on his back and stomach because he was itching really bad. The next day he had a rash on his stomach but not on his back. He has been dealing with a cold lately. About two weeks ago I started giving him cold and cough medicine. Could it be an allergic reaction to that medicine? Would it show this late? Please, I need help! I need to know how to relieve my son. A friend of mine is going to make him some lotion out of pure shea butter and coconut oil and a soap out of shea butter and olive oil. Maybe the Ivory soap I'm using is drying his skin out too much?? HELP!!!!