Can Antacids Higher Than the pH Level for Acids Affect the Soil?

Common Antacids

• Aluminum hydroxide, calcium carbonate, magnesium carbonate, magnesium hydroxide and sodium bicarbonate are some of the most common compounds in antacids. All of these antacids are bases, so they grab hydrogen ions and thereby raise the pH of their solution. When one of these antacid compounds is mixed with an acid like the hydrochloric acid in your stomach, they react to make water and a salt. They are also weak bases as opposed to strong bases such as sodium hydroxide.

Uses

• Some of the same compounds used in antacids are also used to alter soil pH. Application of crushed limestone, for example, is a common treatment for acidic soils; limestones are made from either calcium carbonate or calcium magnesium carbonate, much like the calcium carbonate or magnesium carbonate in many antacids. Aluminum hydroxide isn't typically used to ameliorate soil pH, but it's normally present in soil and is also found in some commercial antacids.

pH Levels

• If the soil pH is too low, adding an antacid or the equivalent would be beneficial because it would help to bring soil pH back within a desirable range. Very high or alkaline pH levels, however, are not desirable either, so indiscriminately adding antacids to your soil is not wise. These kinds of compounds should only be added to soil if its pH lies outside your plants' tolerance range.

Considerations

• While antacids like the kind you buy at the drugstore can indeed increase the pH of the soil, there's no need to use them in that capacity. Drug store antacids may contain other ingredients you don't want to add to your soil, and they come in tablet form, which means you'd need to crush them or grind them up before you could apply them properly. Even more importantly, your local home and garden store already sells products you can apply to change soil pH -- so there's no reason to buy and use antacids instead.