The tongue's color and surface may change as the result of injury, poor oral hygiene, disease, or other factors. Some or most of the tongue may be involved. Many of the changes occur without producing pain or discomfort.
Tongue color changes
The tongue's papillae (tiny, rounded projections) may become discolored if a person smokes or chews tobacco, eats certain foods or vitamins, or has colored bacteria growing on the tongue.
Black discoloration on the top of the tongue may occur if a person takes bismuth preparations for an upset stomach. Brushing the tongue with a toothbrush or scraping it with a tongue scraper can remove such discoloration.
A small blue-black discoloration on the underside of the tongue may be a tattoo caused by a fragment of dental amalgam filling material, which contains silver, becoming stuck in the tongue.
A pale and smooth tongue can be caused by iron deficiency anemia or by pernicious anemia, which is caused by a deficiency of vitamin B12.
A strawberry-red tongue may be the first sign of scarlet fever or, in a child, a sign of Kawasaki disease or multisystem inflammatory syndrome in children (MIS-C), an uncommon complication of COVID-19.
A smooth red tongue and painful mouth may indicate general inflammation of the tongue (glossitis) or be caused by pellagra, a type of undernutrition caused by a (vitamin B3) in the diet.
Tongue surface changes
In geographic tongue, some areas of the tongue are red and smooth (like ulcers), often surrounded by a white border. Other areas, appearing white or yellow and rough, may resemble psoriasis or be caused by psoriasis. The areas of discoloration often move around over a period of weeks to years. The condition is usually painless, and no treatment is needed. If people have symptoms, applying low doses of corticosteroids sometimes helps.
In fissured tongue, deep grooves are located on the tongue surface. The cause is unknown, but fissured tongue may occur with geographic tongue and some other disorders. Usually, there are no symptoms and no treatment is needed.
In "hairy" tongue, keratin (a normal body protein that is in hair, skin, and nails) accumulates on the normal projections on the top of the tongue (papillae) and gives it a hairy appearance. Hairy tongue may develop when food debris is trapped in the papillae when people do not clean their mouth adequately. The tongue may also appear hairy after a fever, after antibiotic treatment, or when peroxide mouthwash is used too often.
These "hairs" on the top of the tongue should not be confused with hairy leukoplakia. Hairy leukoplakia is white, hairy-appearing patches on the side of the tongue that is caused by the Epstein-Barr virus. It usually occurs in people with conditions that suppress the immune system, especially HIV infection.
SCIENCE PHOTO LIBRARY
Photo courtesy of Casey Campbell, DDS, MS.
Photo courtesy of Craig B. Fowler, DDS.
SCIENCE PHOTO LIBRARY
Photo courtesy of Casey Campbell, DDS, MS.
Photo courtesy of Craig B. Fowler, DDS.
Whitish patches on the tongue, similar to those sometimes found inside the cheeks, may be due to
Fever
Dehydration
The second stage of syphilis
Thrush (a Candida infection)
Lichen planus (an itchy skin disease that can also affect the mouth)
Leukoplakia (a flat white spot that develops as a result of prolonged irritation)
Mouth breathing
Rubbing against a sharp tooth edge or broken filling
