Blue or grey skin or lips, medically known as cyanosis, is a symptom that should never be ignored. It often indicates that the body is not getting enough oxygen or that blood circulation is impaired. While it can sometimes be linked to cold temperatures or minor circulation issues, cyanosis can also be a warning sign of serious and potentially life-threatening medical conditions involving the lungs, heart, or airways.
This article explains what cyanosis is, how to recognise it on different skin tones, what causes it, and when to seek urgent medical help. The information is based on guidance from the NHS and is intended to support awareness, not replace professional medical advice.
Cyanosis occurs when there is a reduced level of oxygen in the blood or when oxygenated blood is not reaching certain parts of the body effectively. Oxygen gives blood its red colour. When oxygen levels drop, the blood becomes darker, which can cause the skin or lips to appear blue or grey.
Cyanosis is not a condition in itself. It is a symptom of an underlying problem. Identifying the cause quickly is essential, especially if the colour change appears suddenly or is accompanied by other symptoms.
Cyanosis can affect several areas of the body. The most commonly affected areas include:
On people with black or brown skin, cyanosis may be less noticeable on the face or limbs. It is often easier to see on the palms of the hands, soles of the feet, lips, gums, and inside the eyelids.
Hands and feet affected by cyanosis are usually a normal temperature. However, if poor blood circulation is also present, they may feel cold to the touch.
Cyanosis in babies and children is particularly serious and requires immediate attention. Signs to watch for include:
If a child shows these symptoms, emergency medical help is required.
These signs may indicate a serious medical emergency such as heart failure, severe asthma, pneumonia, or airway obstruction.
You should seek urgent advice from NHS 111 if:
This may be related to circulation problems rather than oxygen levels, but it still requires medical assessment.
Cyanosis happens when oxygen delivery to tissues is reduced or blocked. There are several possible causes, ranging from mild to severe.
Problems with the lungs can reduce the amount of oxygen entering the bloodstream. Common causes include:
When the lungs cannot efficiently absorb oxygen, cyanosis can develop rapidly.
Blocked or narrowed airways prevent oxygen from reaching the lungs. Causes include:
These conditions often require immediate medical treatment.
Heart problems can affect how oxygenated blood is circulated around the body. Conditions linked to cyanosis include:
In these cases, the blood may not be pumped effectively, leading to oxygen deprivation in tissues.
Poor blood circulation can cause cyanosis, especially in the hands and feet. Possible causes include:
Circulatory cyanosis often affects extremities rather than the lips or face.
Certain medicines and external factors can also contribute to cyanosis, such as:
In these cases, cyanosis may improve once the cause is addressed.
Healthcare professionals diagnose cyanosis through physical examination and medical tests. These may include:
Diagnosis focuses on identifying the underlying cause rather than treating cyanosis alone.
There is no single treatment for cyanosis. Treatment depends entirely on the underlying cause.
Examples include:
Prompt medical care improves outcomes, particularly in emergency situations.
Cyanosis is often a visible sign of oxygen deprivation, which can cause serious damage to organs if left untreated. The brain and heart are especially sensitive to low oxygen levels. Even short delays in treatment can lead to long-term complications or death.
Recognising early warning signs and knowing when to seek help can save lives.
Some people live with chronic conditions that can cause recurring cyanosis. Managing these conditions effectively involves:
If cyanosis becomes more frequent or severe, medical advice should be sought promptly.
Blue or grey skin or lips (cyanosis), NHS UK website.
This blog is for informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek advice from a qualified healthcare professional if you are concerned about symptoms such as blue or grey skin or lips. In an emergency, call 999 immediately.
