Symptom blue lips indicates oxygen starvation. Most often it is associated with the disease called cyanosis (from al-Greek. - "dark blue"). The skin and mucous membranes acquire a violet tint due to the increase in the blood of recovered hemoglobin. Cyanosis is a symptom of hypoxemia (reduced oxygen in the blood). Often cyanosis is a sign of heart disease.

The lack of oxygen in the blood can occur from exposure to toxic gases and as a result of frequent Smoking. It also causes the darkened lips.

Cyanosis of the lips, combined with the pallor of the skin appears with iron deficiency anemia. Iron is a vital component of hemoglobin, the substance responsible for the red color of blood. Deficiency of hemoglobin can be caused not only by insufficient iron content in food, but also blood loss during menstruation or stomach ulcer, as well as just a big blood loss resulting in serious injury.

Blue lips in a child combined with a strong barking cough should alert parents – these signs could indicate the formation of severe forms of croup, disorders caused by diseases of the respiratory system.

A drastic change natural lip color to purple when increased heart rate and breath indicates a dysfunction of the heart or lungs. It could be a heart attack, pneumonia, bronchitis, asthma and other diseases, causing oxygen starvation. And the lips may abruptly turn blue when the clot within the vessels of the lungs. In these cases you should immediately consult a doctor.

And finally, the very common cause of blue lips hypothermia. The fact that a lot of blood vessels in the lips of the person when cooled begin to narrow, blood is redirected to internal organs. Due to vasoconstriction in the skin reduces the blood flow, and therefore the skin takes on a bluish tinge. Normal pink skin color and lips provided only to the continuous circulation of blood. When warming the body's blood athinoula to internal organs, returns back and continues to circulate throughout the body, return the lips a pinkish hue.