"I don’t understand why it would be that high that late after taking her Dex.

"Well if taken at 9.30am your only talking 6 hours ago that the dose was taken really and dex is not like HCT or Pred it is many more time potent.  The whole idea is that it does stay up high to provide coverage and it isn’t immediately going to mean you start producing lot’s of 17 OHP when it get’s down to a certain level either--which I think is the labs we’re probably talking about here? 

If you were to take HC at 9.30 for example two hours later it would peak within an hour and then two hours later would be considerably lower at say 12.30pm.  However, because dex is 80 times more potent than HC, if taken at 9.30am and if it peaks within an hour, it will take many more hours before it even get’s to the same level as the HC dose taken at 9.30 achieved within three hours of being taken.  Even when it does drop considerably, it is not right away that adrenals would start to manufacture DHEA’s or 17 OHP to my mind.  It does matter when you get those blood tests done really---you either have to be consistent and take them in the morning, or have them taken at the same time in the afternoon so that you can compare apples with apples.  If you do it morning one month and afternoon the three months later, this does not allow you to compare exactly what the changes are at all because at ANY given time in the day, those lelves are always different anyway depending on how long after the dose you have gone.  So if you get a different reading at every hour of the day---you need to check at the same time if you want to make sure your on track. 

It is like slimming and weighing yourself.  The best time to weight yourself is in the morning when you have not eaten or drunk or put your clothes on.  If you weight yourself in the monring one day and then the next day in the afternoon, you may thing, "Oops I have gained two pounds here!" But the fact is, you have drunk fluids, eaten meals and put on clothes and really you have not gained weight at all.  To see the weight loss you need to weight yourself at the same time every day or week.  It is the same priciple with blood tests after taking replacement corticosteroids.