Blue lips or skin

If a person's skin or lips turn blue, it's usually a sign of low blood oxygen levels or poor circulation.

If a person's skin or lips turn blue, it's usually caused by low blood oxygen levels or poor circulation. It can be a sign of a serious problem, so it's important to seek medical advice.

When blood becomes depleted of oxygen, it changes from bright red to darker in colour, and it's this that makes the skin and lips look blue.

In darker-skinned people, the blue tinge may be easier to spot in the lips, gums and around the eyes.

The medical name for this blue tinge is cyanosis.

What to do

Call for an ambulance or go to your nearest hospital emergency department immediately if you notice an adult or child suddenly turning blue, particularly if they have other symptoms, such as difficulty breathing or chest pain . This could be a sign of a life-threatening problem.

See your doctor if you have cyanosis that comes on very gradually, or affects just the fingers, hands, toes or feet. This is usually the result of a less serious problem with blood circulation, but it should still be checked by a doctor.

Common causes of cyanosis

Some of the main causes of cyanosis are described below, but you shouldn't use this to diagnose yourself – always leave that to a doctor.

Cyanosis that just affects the hands, feet or limbs

If just the fingers, toes or limbs have turned blue and feel cold, it's known as peripheral cyanosis.

The cause is usually poor circulation resulting from:

  • Raynaud's phenomenon – where the blood supply to certain parts of the body, usually the fingers and toes, becomes temporarily reduced when exposed to cold temperatures
  • peripheral arterial disease (PAD) – where a build-up of fatty deposits in the arteries restricts blood supply to the legs
  • beta-blockers – medication commonly used to treat high blood pressure
  • a blood clot blocking the blood supply to or from a limb

Cyanosis that affects the skin generally and/or lips

When all the skin and/or lips have a blue tinge, it's known as central cyanosis, and is usually a sign of low levels of oxygen in the blood. Common causes for central cyanosis are listed below.

A problem with the lungs:

A problem with the airways:

  • choking – read what to do if someone is choking
  • croup – a childhood condition, usually caused by a virus, that affects the airways and causes a barking cough
  • epiglottitis – inflammation and swelling of the flap of tissue at the back of the throat, usually caused by infection
  • anaphylaxis – a severe allergic reaction that can restrict the airways

A problem with the heart:

  • heart failure – where the heart fails to pump enough blood around the body
  • congenital heart disease – a heart defect present at birth that can affect how blood travels around the heart and body
  • cardiac arrest – where the heart stops beating

Other causes:

  • exposure to cold air or water
  • being at high altitude
  • fits (seizures) that last a long time
  • a problem with the blood, such as abnormal haemoglobin (the blood can't take up enough oxygen) or a high concentration of red blood cells (polycythaemia)

Common questions about blue lips or skin

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What causes blue lips and skin?

Blue skin or lips indicate that you may have low blood oxygen levels or poor circulation. It can be a sign of a serious problem, so see a doctor or go to your local hospital immediately if your or your child’s skin or lips turn blue.

Common causes for blue lips and skin (central cyanosis) include:

Sometimes, hands, feet, legs or arms can also turn blue. This is known as peripheral cyanosis and it is usually a sign of poor blood circulation. Blue hands, feet, legs or arms can be caused by a medical condition, such as Raynaud’s phenomenon, a blood clot, certain medicines and, less commonly, from being at high altitude or in cold water or air.

Can cyanosis in newborns be normal?

Cyanosis can be common in newborn infants and caused by several conditions. Some are not serious, but others can be potentially life-threatening.

Acrocyanosis is a harmless type of cyanosis that is often seen in healthy newborns. It is caused by blood vessel changes after birth that can make the hands and feet turn blue. Acrocyanosis appears as soon as a baby is born in healthy infants and can remain for up to 48 hours.

Newborn babies can also have a form of cyanosis, known as central cyanosis, for up to 10 minutes after birth. This is normal and caused by a lack of oxygen in the blood vessels at birth. It should disappear within minutes as the baby starts to breathe and more oxygen enters the bloodstream.

More serious causes of cyanosis in newborns include infections, heart disease and disorders that affect the metabolism or nervous system.

Can you get cyanosis from the cold?

Yes, being in cold air or water can sometimes cause cyanosis.

If you have a condition called Raynaud’s phenomenon, which affects the blood supply to the fingers and toes, you may find that being in the cold can make your fingers and toes turn blue.

Is cyanosis always an emergency?

Some causes of cyanosis are not an emergency. However, because cyanosis is usually caused by low blood oxygen levels or poor circulation, it can be a sign of a serious problem.

See a doctor or go to your local hospital immediately if any part of your or your child’s body turns blue.

Can cyanosis be a sign of cardiac arrest?

Yes. Cardiac arrest (when the heart stops beating) can cause a type of cyanosis called central cyanosis. When this happens, all of the skin and the lips can turn blue because the heart is no longer pumping oxygen-rich blood around the body.

Does cyanosis go away on its own?

Cyanosis is a sign of low blood oxygen levels or poor circulation. It can be a serious sign that needs immediate medical attention to find and treat the cause. It may go away once your blood oxygen levels and circulation return to normal.

See a doctor or go to your local hospital immediately if any part of your or your child’s body turns blue.

Why does cyanosis cause clubbing of the fingertips?

Cyanosis does not cause clubbing of the fingertips. Both cyanosis and clubbing are signs of a problem with your blood oxygen levels and circulation.

Clubbing of the fingertips is when the fingernails curve over the top of the fingers instead of dipping downwards towards the cuticle. This makes the fingernails look unusually curved. Clubbing can be harmless on its own, but it can appear in combination with cyanosis if you have congenital heart disease or certain lung diseases, including lung abscess, bronchiectasis and cystic fibrosis.

These conditions can cause long-term low blood oxygen levels, which your body tries to compensate for by making changes to the fingernail bed. This is why clubbing sometimes occurs alongside cyanosis.

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