By active transport reliant on vitamin D and diffusion, calcium is absorbed in the small intestine. The fractional calcium absorption, or the amount of calcium absorbed over that which is consumed, varies over the course of a person's life, peaking in early childhood, early puberty, and the last two trimesters of pregnancy for women. It then gradually declines as a person ages, with a pronounced decline beginning after menopause for women and the late '50s for men.
There are three different ways that calcium Carbonate works pharmacologically. The small intestine, blood, and stomach are all impacted by calcium. Calcium Carbonate functions as an antacid by buffering the acidic environment of the stomach and neutralising gastric acid. When CaCO3 enters the stomach, it separates into a Carbonate anion (CO32) and ionised calcium (Ca2+).
The stomach's free protons (H+) will then form a bond with the Carbonate anion, raising the pH by lowering the concentration of hydrogen ions. Pepsin, bile acids, and Helicobacter pylori toxins are suppressed by raising the stomach's ph.
