Bluish discoloration of the skin may be due to a lack of oxygen in the blood. It could also mean that there is the presence of an abnormal form of hemoglobin, such as what happens in sickle cell anemia. Bluish lips or skin is also known as cyanosis.
Cyanosis is the result of poor blood circulation due to low levels of oxygen. The bluish discoloration affects the lips, but it can also affect the other parts of the body.
When blood has low levels of oxygen, it becomes darker in color, and it makes the skin and the lips look blue.
Causes
The most common causes of blue lips of skin are lack of oxygen that in the tissues and in the lungs that may be caused by air passage blockage, choking, coughing and lung inflammation.
Lung disease and congenital heart disease can also cause blue lips and skin. The other causes of blue lips are bone marrow disorders that produce excess red blood cells and the other is blood poisoning caused by bacteria. Blue lips and skin can also be due to asthma, bronchitis, emphysema and other lung conditions.