What is the cause of a little purple lips, a little purple lips, if not because of lipstick or pigmentation problems brought about by the phenomenon of mild purple, is cyanosis. Mild purple, that is, cyanosis itself is not very serious, any cause of poor oxygen uptake capacity of hemoglobin, this kind of cyanosis, such as reduced hemoglobin increase or abnormal hemoglobin increase. By reduced hemoglobinosis, we mean that the hemoglobin has become poor in its ability to carry oxygen, or it has not had enough time to carry the oxygen absorbed, so it is classified as peripheral, central, and mixed. The central one is any lung disease brought about by the lungs, which brings about ventilation or ventilation dysfunction and a state of hypoxia, which can bring about central cyanosis. Peripheral cyanosis is caused by stagnant blood flow, mostly due to cardiac insufficiency or congenital heart disease, which causes stagnation of venous blood flow, obstruction of oxygen consumption is significantly increased, the return of blood flow is slowed down or in fact, after the return of the heart, oxygenation is very poor, and then discharged out of the peripheral cyanosis is caused. If the cyanosis is not very severe, it means that the reduced hemoglobin level is not particularly high. Cyanosis can also occur in the presence of abnormal hemoglobinemia, such as methemoglobinemia or hemosulfated hemoglobinemia.