She was on Prednisone (a form of cortisone)for years. Her doctor took her off the pred. about 2 years ago to give her system a break and because she was having problems with bone deterioration in her joints. Honestly, she hasn't really found anything that completely takes care of her Lupus. The pred. just helped control it. She would still wake up hurting all over for no reason, and codeine wouldn't even dull the pain.
Have you tried a combo. of the steroids and tea tree oil? We use a tea tree oil shampoo on our Akitas -- it does seem to help prevent hot spots.
What does your vet say? Have you contacted a veterinary dermatologist?