Hi Beth, I never took Cortef. I went from cortisone to prednisone to dexamethasone. I was switched to dexamethasone when I was 19 (I am 35 now). My endo gave me the same reason. One dexamethasone replaced 4-5 (I can't remember) prednisone. I find it easier to take one dex (.25mg). I haven't noticed any side effects other than I have to keep a close eye on bone density.