A healthy tongue will have a pink or red color and a smooth texture. A green tongue can be a sign of several serious medical conditions.

A tongue with a different coloration or texture than normal may be a sign of disease. Read on to learn the possible causes of green tongue.

A green tongue can have many different causes. Often, a green tongue starts off as a white tongue, but changes to green with time after eating, drinking, or taking certain medications.

Below are some common causes of a green tongue:

Geographic tongue

Geographic tongue causes harmless lesions on the tongue that may change color. Initially, lesions caused by geographic tongue may appear red with raised white borders, but those borders may change to a green color over time.

Other symptoms include:

  • irregular lesions on the tongue that are smooth and vary in shape and size
  • lesions on the tongue that appear to “migrate” or move to one area of the tongue to another over time (over days or weeks)
  • lesions that appear and disappear frequently
  • some mild feelings of discomfort or burning on the tongue or in the mouth

Another symptom of geographic tongue is extra sensitivity on the tongue, especially to certain substances. These substances may include:

  • cigarette smoke
  • toothpaste
  • mouthwashes
  • sugar or sweet food
  • foods that are very spicy or acidic

Learn more about geographic tongue.

Hairy tongue syndrome

Hairy tongue occurs when a certain type of cell on the tongue doesn’t shed as it should. This gives the tongue a rough or “hairy” appearance. This rough surface creates a place for bacteria and yeast to thrive. This can discolor your tongue, causing a green hue.

A color change is even more common after eating certain types of foods or drinks, or using certain products. Other symptoms of hairy tongue include:

  • a burning sensation on the tongue
  • a gagging or tickling sensation caused by the lengthened cells on the tongue
  • bad breath caused by bacteria or yeast growing on the tongue
  • abnormal taste on the tongue, or a lack of taste caused by covered-up taste buds

Learn more about hairy tongue.

Lichen planus

Lichen planus is a rash-like condition that can cause tongue discoloration. Usually lichen planus on the tongue occurs as a white color. It can change green when bacteria or yeast begins to grow on it, certain foods or drinks are consumed, or certain products are used. Other symptoms of lichen planus include:

  • swirling white lesions in the mouth, which might be painful or cause a burning sensation
  • white lesions in the mouth that change color due to bacteria, yeast, food, drinks, or products used in the mouth

Learn more about lichen planus.

Oral cancer

Oral cancers can cause growths and lesions on the tongue that change color when bacteria or yeast begins to grow on it, you consume certain foods and drinks, or when you use certain products in your mouth. Symptoms of oral cancer include:

  • a sore or lesion on the tongue that won’t heal
  • a mass or growth on the tongue
  • bleeding on the tongue
  • dramatic weight loss
  • numbness in the lower lip, face, neck, or chin
  • patches on the tongue that are white, red and white, red, or green

Learn more about oral cancer.

Oral thrush

Oral thrush is an overgrowth of yeast on the tongue and inside the mouth. It’s caused by an overgrowth of fungus naturally found in the mouth. This fungal overgrowth looks white, but can turn green over time as the infection sets in. Other symptoms of oral thrush include:

  • white bumps on the tongue or tonsils
  • bleeding when the bumps in the mouth are scraped by the teeth or a toothbrush
  • pain at the location of the bumps in the mouth
  • trouble swallowing

In infants, symptoms of oral thrush include trouble feeding, fussiness, and irritability.

Learn more about oral thrush.

The treatment for green tongue depends on its cause. In most cases, the cause is bacteria, fungus, or yeast. In these cases, treatment may include antifungal medication. Options include:

These at-home tips can also help your tongue recover from a bacterial, fungal, or yeast overgrowth:

  • Brush your teeth softly to avoid irritating lesions in the mouth.
  • Replace your toothbrush every day until the infection goes away.
  • Avoid mouthwashes or sprays.
  • Rinse your mouth with a saltwater solution.
  • Keep your blood sugar levels healthy if you have diabetes.
  • Eat plain yogurt to help rebalance the levels of good bacteria in your body.

When green tongue is caused by inflammation, treatment may include:

  • corticosteroids to reduce inflammation
  • antihistamines to reduce inflammation and stop an allergic reaction
  • over-the-counter pain relievers, such as ibuprofen (Advil)

For green tongue caused by inflammation, avoid foods and drinks that cause irritation to the mouth. Also avoid products that irritate your mouth, such as flavored toothpastes.

When the cause of green tongue is cancer, treatment depends on the stage, type, and exact location of the cancer. Treatment may include:

For all cases of green tongue, proper treatment involves good oral hygiene. Brush your teeth at least twice a day, and ideally after every meal. Flossing is another important part of good oral hygiene.

While green tongue has many causes, it’s often a sign of a bacterial, fungal, or yeast overgrowth. If there are lesions in the mouth, these substances can cause serious infections. It’s important to seek treatment for a green tongue right away.

In most cases, green tongue will go away quickly with proper treatment. Be sure to follow your doctor’s treatment plan to ensure the best possible outcome.