If you have bitterness in your mouth, you should usually consider whether it is caused by improper oral cleaning, bitter food, mental stress or fire, which will usually be relieved on its own after adjusting your diet and rest. However, if the bitterness in the mouth persists, it is necessary to go to the hospital to check whether it is caused by diseases. The common clinical causes of bitterness in the mouth are the following: 1, oral diseases: If the patient has daily cleaning teeth in place, long-term smoking, mental stress, etc., it is easy to cause oral inflammatory diseases, such as periodontitis, gingivitis, oral ulcers, is likely to cause the symptoms of bitterness in the mouth, may also be accompanied by bleeding gums, swelling, pain, bad breath, etc.. In this case, it is recommended that patients go to the hospital’s Department of Dentistry for treatment. If the inflammation is the cause, oral rinses are usually performed to eliminate the inflammation, and scaling can be performed if necessary. After oral diseases are controlled, the discomfort will gradually improve; 2. Gastrointestinal diseases: If patients have bad habits such as overeating, long-term late-night snacking, staying up late, or when there is Helicobacter pylori infection, it may cause gastrointestinal disorders, gastritis, gastric ulcers and other diseases, which will also cause bitterness in the mouth, and will be accompanied by abdominal pain, bloating, constipation, nausea, vomiting and many other discomforts. After the diagnosis is confirmed, the symptoms of bitterness in the mouth will be improved after the clinical treatment is usually targeted according to the cause. Commonly used drugs include gastric mucosal protective agents, prokinetic drugs, drugs to inhibit gastric acid secretion, and antibiotic drugs for the treatment of Helicobacter pylori, common drugs such as omeprazole, aluminum thioglycollate, domperidone tablets, bifidobacteria, clarithromycin, etc.; 3. Liver and biliary diseases: If the patient has abnormal liver function, gallbladder metabolic disorders, such as excessive bile secretion, it will also cause bitterness in the mouth. Common clinical diseases such as cholecystitis, gallstones and cirrhosis may also be accompanied by nausea, vomiting, skin yellowing, ascites, edema and other symptoms after the onset. Patients need to seek prompt medical attention and receive treatment. In addition, diseases such as hypertension, diabetes and nephritis may also cause bitterness in the mouth. Patients are advised to consult a doctor and receive symptomatic treatment if they experience persistent bitterness in the mouth. Daily life should also pay attention to good living habits, light diet, regular rest and rest, adhere to outdoor exercise, good personal cleanliness and hygiene, etc.