What Causes Blue or Purple Lips?

Updated July 14, 2022
Scandinavian looking blond woman looking very cold, frozen in the winter

You may have noticed that your lips turn purple or blue in the cold, or you may have seen a baby or someone else with bluish or purplish lips. In many cases, this type is caused by cyanosis, which is a discoloration of a part of the body resulting from a lack of oxygen in the blood.

Cyanosis can occur for various reasons, and it's not the only possible cause of blue or purple lips. Both lifestyle conditions and illnesses can lead to lip discoloration.

Lifestyle Factors That May Cause Blue or Purple Lips

In some cases, lifestyle factors related to environmental conditions can cause a person's lips to take on a blue or purple hue. Examples of lifestyle factors that may occasionally be to blame for lip discoloration include:

Cold Weather

Spending too long in cold weather without proper clothing can cause lips and skin to turn blue. Such a change in lip color as a result of cold exposure can be a sign of hypothermia. If this occurs, follow hypothermia first aid care procedures and seek assistance from a qualified medical professional. Avoiding exposure to extremely cold weather, or dressing properly in warm clothing can help prevent blue lips from this cause.

Altitude Sickness

When in higher altitudes, such as when mountain climbing, altitude sickness is a risk. The air at higher altitudes has less oxygen, and a lack of oxygen can lead to cyanosis. Altitude sickness can be serious, even fatal, but can be prevented by slowly acclimating to high altitudes. Severe altitude sickness is a medical emergency that is often treated by descending to a lower altitude, medications, and administering oxygen.

Possible Illness-Related Causes for Blue or Purple Lips

Lip discoloration is not always related to medical factors. When a person's lips turn blue or purple, that can be a sign of a medical condition. Illness-related reasons for purple or blue lips can be serious, so it's important to seek medical attention to help identify and remedy the condition.

Raynaud's Phenomenon

Raynaud's phenomenon, which is sometimes called Raynaud's disease or Raynaud's syndrome, causes a lack of blood flow to the extremities. Raynaud's usually affects fingers and toes, but can also impact lips. It results in a lack of oxygen (cyanosis) that causes a blue or purple color. Raynaud's can be treated by avoiding possible triggers, such as smoking, stress, certain medications, and exposure to cold. In many cases, Raynaud's is associated with another condition. Treating the underlying condition can help with symptoms of Raynaud's phenomenon.


Man is Having Asthmatic Problems Outside in Nature

Asthma is a condition that causes inflammation in the lungs and results in the inability to breathe properly. During an asthma attack, the skin or lips may turn blue because of a lack of oxygen in the body. Asthma could be triggered by stress, cigarette smoke, exercise, or allergens such as animal dander, pollen, or mold. Cyanosis is a sign of a severe asthma attack that needs immediate medical attention. Treatment of asthma can include medications, as well as avoidance of potential triggers.


Croup is a common childhood infection in the upper respiratory system that affects children. Croup is infectious, and can cause symptoms of a barking cough and a "raspy" sound while breathing. Bluish discoloration of the skin is a symptom of severe disease, which needs emergency medical attention. Intravenous dexamethasone and corticosteroids are commonly used to treat severe croup.

Chronic Obstructive Pulmonary Disease (COPD)

COPD is a condition of the lungs that causes airflow obstruction. The lungs are not able to exhale fully, making it more difficult to breathe, and decreasing the amount of oxygen in the body. This lack of oxygen is a chronic condition that can lead to cyanosis in some cases. Many cases of COPD are caused by smoking cigarettes, but it can also rarely be a hereditary condition. COPD is often treated with smoking cessation, inhaled medications, corticosteroids, oxygen therapy, pulmonary rehabilitation, and (infrequently) surgery.

Pulmonary Embolism

When an artery in the lungs is blocked, it is called a pulmonary embolism. The blockage could be from one of a number of reasons, including a blood clot. With an artery blocked, blood flow is going to be inhibited, which results in a number of symptoms, including cyanosis. The purple or blue color could be extensive, affecting the skin and the lips. A pulmonary embolism is a very serious condition that requires immediate treatment. If the embolism is caused by a blood clot, the treatment will include blood thinning medication to dissolve the clot. The cyanosis should resolve with successful treatment of the embolism.

Congenital Heart Defects

A congenital condition is something that a person is born with. Therefore, a congenital heart defect could affect newborns, who may have a purple or bluish tint to their skin or lips after birth. Adults may also be affected, as the defect may not cause any signs or symptoms until later in life when the heart is under more stress. Any congenital heart defect, but especially those that are called cyanotic defects, can result in blue or purple lips. Treating a congenital heart defect will depend on the nature of the condition, but could include anything from medication to surgery.


In methemoglobinemia, the body makes too much of a specific form of hemoglobin, called methemoglobin. Due to the high levels of this type of hemoglobin, oxygen isn't released into the body properly. This can result in cyanosis. Methemoglobinemia can be inherited. It can also be caused by medications or foods containing nitrites. In mild cases, discontinuation of the medication or food is the only treatment. More serious cases may need treatment with medication or a blood transfusion.

What To Do If You Have Purple or Blue Lips

If you experience an unexplained blue or purple discoloration of your lips, it is essential for you to speak with your physician or seek medical treatment right away, as showing signs of cyanosis is not a symptom to take lightly. In some cases, the presence of cyanosis can be a serious medical emergency that requires immediate treatment.

What Causes Blue or Purple Lips?