As soon as you drink coffee, your stomach hurts as a result of gastric neurosis, chronic gastritis and gastric ulcer. Coffee contains a large number of substances such as caffeine, which has the effect of uplifting the spirit and eliminating fatigue. But too much coffee can cause stimulation of the plant nerves and even lead to plant nerve dysfunction, thus triggering gastric neurosis. Some people will experience slow gastric peristalsis or even stop peristalsis during the attack of gastric neurosis, and this will lead to gastric distension and stomach pain. The chronic gastritis patients are relatively sensitive because there is congestion and edema on the gastric mucosa, and the caffeine in coffee has a certain irritation. When patients with chronic gastritis drink coffee, it will cause the gastric mucosa to become more congested and edematous, thus inducing stomach pain. Caffeine will stimulate excessive secretion of gastric acid, and patients with gastric ulcer disease, there is an ulcerated surface on the gastric mucosa, gastric acid on the ulcerated surface caused by the violation of the stomach pain will be triggered.