The side effects of oral sodium bicarbonate tablets are mainly seen in: 1. Abdominal flatulence. As a result of taking sodium bicarbonate tablets, sodium bicarbonate and gastric acid in the stomach play an acid-base reaction and produce a large amount of carbon dioxide, a large amount of carbon dioxide in the stomach can appear in the increase of flatulence, belching and other side effects. 2, indigestion. Long-term use of sodium bicarbonate tablets can inhibit the secretion of pepsin in the stomach, and the reduction of pepsin can increase the digestive burden of the stomach, resulting in indigestion. 3, secondary to increased secretion of gastric acid. Sodium bicarbonate does not inhibit the secretion of stomach acid, but only plays the role of neutralizing stomach acid in the stomach, but at the same time, the secretion of stomach acid in the stomach will also increase accordingly, temporary use can neutralize stomach acid and improve the symptoms, long-term use will lead to excessive secretion of stomach acid and heartburn, acid reflux symptoms.