I have a 9 year old son who is SWCAH.  I just had this conversation with our endo a few weeks ago. 

She explained it this way to me.  Cortef, Dexamethasone then Prednisone.  That is the order of their strengths.  Cortef should be given three times a day.  You would move up in strengths in order to decrease the amount of dosages per day.  She told me that you typically do this when the patient is older because they become careless about taking it three times a day.  Dexamethasone would be twice a day.  Prednisone one to two times a day, depending on the dose.  She said that if my son were to stay dependable about taking his Cortef 3 times a day when older then he would not be changed. 

As for symptoms I’m sorry that I can’t shed light there as my son is on Cortef 3 times a day and has never had an issue other than once.  We forgot his meds one morning before school.  He got his mid day at school but he was very sick that night, fever, headache and generally not feeling well that evening until he got his meds after school.

Judy