my son 6 years of age has been itching all over since tue jan 26th. No rash of any kind. scratching so bad making welts on him. no hives. itching comes and goes. have not changed anything, or has he ate anything new. he has no allergies that I am aware of. have bathed him in aveno oatmeal bath X3. Thought it may just be dry skin. have been putting lotion on him daily since with no relief. any suggestions?