How Can Skin Rashes Be Treated?

For three years I have been battling skin lesions. I ve seen several mds including three dermatologists. One just told me I have lesions because I scratch. I didn t have this always. Was first diagnosed as allergic/reactive red cortisone creams. Got some better, for a while, then got slowly worse. Which it has continued to do in response to any therapies. Was treated for fungal infection, improved but never completely. Have been on keflex, same, then doxycycline. My skin has become so chronically irritated that I only use coconut oil; all else itches like crazy in a few hours. Current Dermatologist appears to think my symptoms make no sense and I am probably a Crack pot. I talk very little about it but finally told a friend who said I might have dietary deficiency especially hyaluronic acid. How do I find out? Theresa Roger s Springfield Oregon