A bout of stomach pain is usually due to stomach cramps, gastrointestinal dysfunction or chronic digestive diseases, as follows: 1. stomach cramps, strong contraction of the stomach muscles will lead to stomach cramps, mostly manifested as sudden and severe pain, usually due to irregular diet, overeating or eating too much irritating, too cold, too hot food. 2. gastrointestinal dysfunction, mostly related to mental factors, if long-term If you are in a state of mental tension, anxiety or emotional instability, it will stimulate the cerebral cortex, leading to gastrointestinal dysfunction; biological and social factors also play a role in the disease. 3, chronic digestive diseases, chronic gastritis, duodenal ulcer, gastric ulcer and other diseases, the disease is long, often recurrent, and persistent. In the attack there will be discomfort in the upper abdomen, manifested as abdominal distension and pain, accompanied by nausea, belching, vomiting, acid reflux.