If it is necessary to differentiate cleft lip between Chinese medicine and western medicine, if it is caused by fire syndrome and inflammation from the perspective of Chinese medicine, it is usually caused by excessive internal heat. From the point of view of western medicine, cleft lip has the following factors: 1, lack of vitamins and trace elements, and usually lack of vitamin B can easily lead to cleft lip. 2, contact dermatitis, cleft lip will also appear. 3. Infectious factors, such as bacteria, viruses or other pathogenic microorganisms, will cause fever, fever and other reactions when they infect the body, and the clinical symptoms of cleft lip will appear when they have fever or fever. 4. When allergic reaction occurs, if the lips are allergic to chemicals such as capsaicin or allergic substances, cleft lip will also occur. 5. If the patient is seriously dehydrated, there will be clinical symptoms of cleft lip. There are many reasons for cleft lip, such as lack of vitamins, especially vitamin B2 riboflavin, which can lead to angular stomatitis and chapped lips. Also, it is a bad habit to cause lip moisture loss. For example, people who often lick their lips will have water volatilized after their lips are air-dried, making them dry. Many people feel that the drier they are, the more they want to lick their lips, and the drier they are after licking their lips. So I think dry lips can be protected by applying grease lip protection, including sesame oil or lip balm, and don't lick your lips too much. There are also chapped lips caused by external environment, such as chapped lips caused by windy sand and low air humidity. There is also lipstick allergy, which causes swelling after allergy, and chapped lips will appear after swelling subsides.