The normal lip color is mostly pink, if the red color is too bright or deep purplish red, the lips are flushed. Under pathological conditions, such as the occurrence of inflammation of the oral mucosa, or bacterial infectious diseases, cardiovascular diseases, digestive system diseases, etc. Differential diagnosis: Pathological flushing of the mouth and lips needs to be distinguished from flushing of the mouth and lips caused by poisoning. This symptom is also associated with various types of poisoning, such as heavy metals, chemical agents, and plant toxins. For example, in carbon monoxide poisoning, the main symptoms are flushing of the lips and mouth, cherry red, dizziness, headache, tinnitus, palpitations, nausea, vomiting, weakness, and so on. It needs to be promptly identified and emergency treatment measures taken. For patients with flushed lips, there are many causes of the symptoms. The color, luster and texture of the lips change without fail to reflect the health condition of the body. Once there are changes in the lips, it may indicate that there is something wrong with the body. Pathological causes, such as inflammation of the oral mucosa, or bacterial infectious diseases, cardiovascular diseases, digestive system diseases, etc. may also accompany the appearance of this symptom. Therefore, when diagnosing, attention should be paid to examining and confirming the diagnosis in the context of the functional status of the whole body to avoid missing or misdiagnosis. Prevention of flushing in the mouth and lips: In general, it may be caused by what is commonly known as “fire” in the body. If it is accompanied by bad breath and eructation, it means dampness and heat in the spleen and stomach; if it is accompanied by distension and anorexia, it means that the liver fire is too strong. It is important to prevent the flushing of the lips and mouth according to the specific causes of the symptoms.