Since the 5 mg is the amount your adrenal glands would be producing naturally (if they were still working), I do expect your face will go back to normal with that amount.
I was on 5 mg a while on my way off prednisone, unfortunately I don't remember when the moon face started to disappear.
It will help if you drink plenty of water and try to restrict carbs & sugars (at least the white ones!).
Lynnwood, Lupus & Sjogren's Moderator, Dx: 2002DIAGNOSING LUPUS & HW's LUPUS 101
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