You may also ask them if it is an intolerance or a true allergy.
If it is an intolerance, some wheat-sensitive individuals can use wheat-hybrid grains like Kamut and spelt. It depends on if their sensitivity is to the actual gluten or the gliaden (the other component of the starch).
If it is a true allergy, these subs may not work.
rice flour is difficult to bake with. I tasted some bread made with it and I tossed it out for the birds don't want to scare you off.
Maybe you could find some recipes using cornmeal, buckwheat (it's really a grass), etc.
Thoreau said, 'A man is rich in proportion to the things he can leave alone.'