Alright, serious talk. There are spells that can remove one's nose, but unfortunately I've never learned them.
There are methods to stop yourself from sneezing that we've been taught to tell patients. Besides the obvious stay away from allergens or strong scents, if she feels a sneeze coming on she can 1) think about how you're about to sneeze... sometimes that does the trick, 2) pinch your nostrils closed, 3) blow your nose.