When there is excessive stomach fire, it can cause oral ulcers. This is because excessive stomach fire leads to poor digestion in the gastrointestinal tract, where food cannot be digested in time and regurgitates into the mouth. It can also cause throat pain and oral inflammation, so it is crucial to treat stomach fire promptly. For severe cases, medication that improves stomach fire should be taken, and for mild cases, the condition can be managed through diet. Eating more watermelon, apples, and similar foods can help reduce stomach fire. Most importantly, avoid alcohol, smoking, and staying up late. (Medication should be taken under the guidance of a professional doctor.)