Baking soda. Baking soda neutralizes stomach acid, according to Jacqueline Wolf MD, an associate professor of medicine at Harvard University. Baking soda should only be used occasionally by adults or teenagers. The recipe to combat heartburn is ½ teaspoon baking soda dissolved in a four-ounce glass of water. An individual can repeat this treatment every two hours approximately five or six times. Too much baking soda can have negative health effects but using the suggested amount can provide immediate relief.