Summarize this article in one sentence.
One of the easiest substitutes for baking soda is baking powder. If you have baking powder in your cabinet, simply add triple the amount of baking powder to your recipe. For example, if your recipe calls for one tablespoon of baking soda, add three tablespoons of baking powder. You can substitute baking powder for baking soda in pretty much any recipe that requires baking soda. If you're out of baking powder as well, check to see if you have self-rising flour. Self-rising flour contains a small amount of baking powder, so it can also be used as a baking soda substitute. Simply replace the regular flour in your recipe with self-rising flour. If you don't have baking ingredients to use as substitutes, check your medicine cabinet for potassium bicarbonate. This is a medication sometimes used to treat conditions like acid reflux or hypertension. For each teaspoon of baking soda in a recipe, add one teaspoon of potassium bicarbonate mixed with a third a teaspoon of salt. This usually works out best when baking cookies. It may not work out as well for recipes like cakes, pancakes, muffins, and other baked goods.

Summary:
Use triple the amount of baking powder. Use self-rising flour. Mix potassium bicarbonate and salt.