CHARLES D. WINTERS / SCIENCE PHOTO LIBRARY CHARLES D. WINTERS / SCIENCE PHOTO LIBRARY
Alka-Seltzer. View of an Alka-Seltzer tablet effervescing as it dissolves in water. Alka- Seltzer is a non-prescription proprietary antacid. Each tablet contains sodium bicarbonate, citric acid and aspirin. The sodium bicarbonate is present as a fast-acting acid-neutralising compound. The citric acid is used to promote effervescence of the tablets in solution, and to prevent 'acid rebound' (over-production of stomach acids following the dose of bicarbonate). Aspirin is included as a mild pain reliever, its speed of action is promoted by the carbon dioxide generated by the reaction of the bicarbonate with stomach acids and the tablet's citric acid.
Model release not required. Property release not required.