Thanks for your response. It does make more sense that her cortisol level would be low, since it has been suppressed, although maybe 2 mgs is not enough to be suppressive. My guess is that, since the prednisone helps her chronic hives, and that got somewhat worse the day she was off pred, her body was just really over compensating and stressed by doing without. Maybe this proves that she doesn’t have LOCAH; as you say, how could she produce that much? On the other hand, I’m wondering if the results are reliable at all. I’d really like to know that because I’d hate for her to be treated based on an inaccurate result. I did find out that the Yasmin she takes (or any bcp) can increase cortisol levels.