If you have bitterness inside your mouth after eating, you should first consider whether you have digestive malfunction or bile reflux, and you can first undergo a series of tests to assess whether you have any corresponding diseases. For example, liver and gallbladder ultrasound and gastroscopy can be performed to confirm whether bile excretion is abnormal due to biliary tract diseases or bile reflux into the stomach, causing symptoms in the stomach, and whether gastritis or gastric ulcer is present, causing gastrointestinal digestive malfunction. If these diseases are present, the symptoms of bitter mouth may be relieved with further appropriate treatment. In addition, it is also necessary to pay attention to dietary regulation and improvement of living habits, not to stay up late, smoke and drink, and to reduce greasy, fried, spicy and stimulating foods. We should also pay attention to oral care, give active treatment when there are corresponding abnormal infection foci in the mouth, and take the initiative to brush teeth and rinse the mouth, etc. After a combination of various factors, it is possible to relieve the symptoms of bitter mouth.