The solution to acid in the mouth is to adopt different treatments according to different causes, which mainly include gastroesophageal reflux disease (GERD), poor oral hygiene, gastritis and so on. 1. Gastroesophageal Reflux Disease (GERD): GERD is mainly due to excessive secretion of gastric acid, intestinal peristalsis is slower, which leads to the reflux of gastric acid into the esophagus, resulting in acid in the mouth, which can be accompanied by heartburn and other symptoms, you can take omeprazole enteric-coated capsules, lansoprazole enteric-coated tablets, rabeprazole sodium enteric-coated tablets and other drugs. 2. Pay attention to oral hygiene: after consuming ice cream, sugar cubes and other foods with too much sweetness, there is no timely rinsing and brushing, and the fermentation of food residues may lead to sour breath. It is recommended to pay attention to oral hygiene, brush your teeth in the morning and evening, and use mouthwash appropriately. 3. Gastritis: gastritis may be due to gastrointestinal infection caused by Helicobacter pylori excessive secretion of gastric acid, which can cause turbidity upward, thus causing the phenomenon of sour mouth, you can take ranitidine hydrochloride capsules, teprenone capsules, cimetidine tablets and other drugs. If the situation is serious, it is recommended to go to the hospital for examination, to clarify the cause of the disease and timely symptomatic treatment.