Purple lips in girls are mainly seen in the following diseases: 1, diseases of the cardiovascular system, the most common are ventricular septal defect, arteriovenous catheterization, etc.. A large amount of venous blood enters the arterial system directly through this abnormal channel and thus enters the blood circulation in all parts of the body. 2, pulmonary causes, such as pneumonia, pulmonary embolism and other diseases, because the arterial blood is not able to carry out effective oxygenation in the lungs, thus causing the body to be in a state of oxygen deprivation can also appear purple lips. 3, other Diseases, the most common is methemoglobinemia, this disease can lead to abnormal function of hemoglobin, losing the ability to bind oxygen. Thus, it is not able to effectively transport oxygen to various organs and tissues of the body, resulting in oxygen deficiency and purple lips and other symptoms.