Lips purple generally still consider the body may have certain problems, the most common problem is the lung problem, that is, there may be a certain amount of hypoxia, in chronic lung disease, especially chronic obstructive pulmonary disease, asthma acute exacerbation, patients with chronic hypoxia or already exist in respiratory failure, will appear lips purple. Also, plateau hypoxia. There are also children who have darkened lips, and it is important to consider whether the patient may have congenital heart disease, but generally parents are more aware of this. Then there is the cold, if there is a drop in temperature at a particular time, for example, the lips appear purple outside, most of them are because the cold stimulates the vasoconstriction of blood vessels, and there is also anemia, coupled with the stimulation of the cold. If angina or cerebrovascular disease occurs, the lips will also appear purple, and should not be ignored digestive disorders, the patient may usually have constipation, diarrhea, loss of appetite performance, the color of the lips may also be relatively dark. Studies have found that chronic hypoadrenocorticism, there may also be purple skin of the mouth. Young people now bad habits, such as staying up late, excessive smoking, drinking alcohol, may see the person’s breath is not good, the color of the lips will also be purple.