I also have dry itchy skin especially in the winter months. Use a moisturizer (Aveeno) after every shower and it helps. My nephew who lives in New Hampshire uses Vaseline after showering to keep moisture in his skin. About two years ago I had a dry very itchy scalp and doctor prescribed Selenium Sulfide Suspension USP 2.5% shampoo. Not sure how often I had to use it but it worked very well to control the itch. In the winter I often get cracks in the
skin on my hands, CeraVe renewing SA cream helps to heal and prevent cracks. If CeraVe doesn't work, I use Vaseline and white cotton gloves at bedtime which usually does the trick. Unfortunately i believe dry itchy skin is a common side effect of diabetes.