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antacid,any one of several basic substances that counteract stomach acidity (see stomachstomach,
saclike dilation in the gastrointestinal tract between the esophagus and the intestines, forming an organ of digestion. The stomach is present in virtually all vertebrate animals and in many invertebrates.
..... Click the link for more information. ). Antacids are used by physicians to treat hyperchlorhydria, i.e., the excessive production of hydrochloric acid by the parietal cells lining the stomach. Commonly used antacid preparations, most sold without prescription, contain sodium bicarbonate, magnesium hydroxide, or aluminum hydroxide. Some preparations contain substances such as magnesium trisilicate that reduce the formation of gas.
Any substance that counteracts or neutralizes acidity.
1. a substance used to neutralize acidity, esp in the stomach
2. having the properties of this substance