There are lots of yeast-free products available in good health food shops and organic stores. Yeast can cause lots of allergies, and to be on the safe side, try making your own yeast-free bread.
Take 3 cups of wholewheat flour, 4 tsp baking powder, 1 teaspoon salt, 1 1/2 cups milk or water, 1/4 cup of liquid fat, such as melted marg or oil. Mix the dry ingredients together. Then mix the liquids and stir until there is no more dry flour. Shape into a ball and place on a baking sheet and bake for 40 minutes at 400F/ 200C.