Blue Fingernails: What Causes It And When To Get Help

According to the Mayo Clinic, fingernails are made up of a tough, fibrous protein called keratin, and grow outward from the base of the nail. For many people, healthy nails are a cosmetic concern; however, nails play an essential role in protecting the fingers and toes from injury and guarding the body against the entrance of bacteria and viruses, according to Healthline.

Various factors can influence the condition of your nails and provide important clues about underlying health conditions, warns the Mayo Clinic. Changes in nail color, texture, or shape can sometimes indicate underlying health conditions. Indeed, it can be frustrating to watch a perfectly manicured nail change color, leaving you with an unsightly and sometimes painful problem. That said, knowing the reason behind your nail change can help you address or prevent it. 

If your nails take on a blue or purple tinge, this is known as cyanosis — and this symptom can arise due to multiple underlying factors (via the Cleveland Clinic).

Potential causes of cyanosis

According to the Cleveland Clinic, cyanosis is caused by a lack of oxygen in the blood, which results in the blood appearing darker and bluer than usual. There are three types of cyanosis: peripheral, central, and circumoral cyanosis. Peripheral cyanosis occurs when there is a decrease in blood flow in the hands and feet. Central cyanosis occurs when there is a decrease in the amount of oxygen in other parts of the body, alongside the hands and feet. Lastly, circumoral cyanosis occurs only in the mouth and lips.

There are several possible causes of cyanosis, of which cold weather is one. When the body is exposed to cold temperatures, the blood vessels in the fingers and toes constrict, reducing blood flow and oxygen supply to these areas. This can result in blue or purple discoloration of the skin and nails. 

Various medical conditions that can impede your heart or lung function — such as congestive heart failure, heart defects, asthma, respiratory infections, or pneumonia — may also cause cyanosis. Raynaud's disease is another possible culprit. This condition causes blood vessel spasms and reduces blood flow to the hands, typically in response to cold or stress (via Mayo Clinic).

How is cyanosis treated?

The treatment for cyanosis, or blue fingernails, depends on the underlying cause. Once that cause is determined, your doctor can help develop an appropriate treatment plan to address the issue. For example, in cases where cyanosis is simply caused by exposure to cold temperatures, warming the affected area is typically enough to restore normal blood flow and oxygen supply, says the Cleveland Clinic. However, in cases where cyanosis is caused by a medical condition, treatment will focus on addressing the underlying issue in order to improve your circulation. Treatment may also involve supplemental oxygen therapy to increase oxygen levels in the blood.

If, after a diagnosis, your doctor suspects you have Raynaud's syndrome, treatment may involve avoiding triggers, such as cold temperatures or stress, explains the Mayo Clinic. Medications that help dilate blood vessels, such as calcium channel blockers, may also be used to help improve blood flow and reduce symptoms.

If you have cyanosis accompanied by other symptoms such as trouble breathing, pain in the chest, headache, fatigue, and numbness in the extremities, you should seek emergency medical treatment. Infants who have cyanosis and also appear to be limp, tired, grumpy, or are struggling to breathe or eat should also be taken to the emergency room right away.