Has she had her 17 ohp levels tested lately?  If she is not oversuppressed I don’t think the med’s would be causing the problem.  My 4 month old son is (unfortunately) on 10 mg of cortef /day.  We are beginning to worry that he is a high metabalizer because even on this high dose his 17 ohp is still out of control.  He takes 5mg at bedtime and sleeps from 11:00 p.m. to 7:00a.m. without waking.  A couple of weeks ago he started waking at 1:00 and 4:00a.m..  The first couple of nights I was feeding him but then I realized he was eating less and less at his next feeding in the morning.  For a couple of nights I let him fuss for a while and he would fall back to sleep (after 20-30 minutes).  Now he sleeps straight through again.  I think his internal clock was just stuck at this 4:00 a.m. wake up time.  Now he wakes up really hungry and much more rested.  He also does not sleep much during the day.  He usually takes three 30-45 minute naps.   

best wishes!!!  Lisa