julia,

my daughter is 4. she has 21 hyd def salt wasting.  she also has a problem with weight and we have done everything possible to provide her with a good diet.  about 1 month ago we started circadian rhythem dosing of her cortef which includes a 3am dose.  we are hoping with this dosing schedule we can reduce her total dose.  many people on this board have used this method and have had good results.  it is still too early for us to see a difference but i will keep you posted.  you may want to research this and discuss it with your endo.  good luck