Purple Tongue: Causes, Symptoms & When to Seek Medical Help

There is no condition that causes the tongue to turn purple.

If the tongue is purple it could indicate cyanosis, which is caused by a lack of oxygen in the blood. Cyanosis can be a symptom of a serious underlying condition, such as heart disease, lung disease, or carbon monoxide poisoning. If you are experiencing cyanosis, you should seek medical attention immediately.