The main causes of gastric nausea are as follows: 1, the performance of acute gastritis: this condition is often seen in the cold, cold or irregular diet caused by poor digestion, resulting in acute gastric mucosal damage caused by symptoms. 2, the symptoms of chronic gastritis: most of them are due to their own gastric dysfunction, or gastric ulcer, duodenal bulb ulcer resulting in poor digestion, causing nausea, recurrent acid reflux, belching and other symptoms are also common. 3, other diseases can bring up the gastrointestinal symptoms: such as early pregnancy reaction, or cranial nervous system, etc., easily lead to gastrointestinal digestive malfunction, or nausea symptoms. Therefore, if the gastrointestinal symptoms appear, the first thing to do is to exclude digestive system diseases, and you can improve the gastroscopy.