My 18 yr old daughter still takes cortef twice daily.  In fact, at the last labs she did, she looked "too good" (oversuppressed) and the endo dropped her dose from 15mg am and 15mg pm to 15mg am and 10mg pm.  The only issue she has is weight and she fights it constantly.  She is 5’3" tall and probably weighs about 150 - 160.  The dr didn’t want to switch her to prednisone or dex because she didn’t want to cause a bigger weight issue with her.