Calcium carbonate is a basic substance, since it has a pH greater than 7. Substances with a pH level of 7 are neutral, and substances with pH levels less than 7 are acidic.
Calcium carbonate is a chemical compound with various medicinal and industrial uses. Because calcium carbonate contains alkaline ions that help neutralize acids, it's widely used as a gastric antacid. However, calcium carbonate should only be taken with a doctor's approval, since it can be dangerous to those who have medical conditions, such as hypercalcemia or kidney disease. In addition, dangerous drug interactions may occur in patients who are on medications, such as Lanoxin and Didronel.