Traumatic injury is the most common cause of tongue discomfort. The tongue has many nerve endings for pain and touch and is more sensitive to pain than most other parts of the body. The tongue is frequently bitten accidentally but heals quickly. A sharp, broken filling or tooth can do considerable damage to this delicate tissue.
An overgrowth of the normal projections on the top of the tongue (villi) can give it a hairy appearance. 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 forms on the side of the tongue and is characteristic of AIDS.
The tongue's villi may become discolored if a person smokes or chews tobacco, eats certain foods, or has colored bacteria growing on the tongue.
The top of the tongue may look black 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.
Iron deficiency anemia may make the tongue look pale and smooth. Pernicious anemia, which is caused by a deficiency of vitamin B12, may also make the tongue look pale and smooth. The first sign of scarlet fever may be a change from the tongue's normal color to a strawberry, and then raspberry, color. A strawberry-red tongue in a young child may also be a sign of Kawasaki disease. A smooth red tongue and painful mouth may indicate pellagra, a type of undernutrition caused by a deficiency of niacin (vitamin B3) in the diet. A red tongue may also be inflamed (glossitis)—the tongue is red, painful, and swollen.
Whitish patches, similar to those sometimes found inside the cheeks, may accompany fever, dehydration, the second stage of syphilis, thrush, lichen planus, leukoplakia, or mouth breathing.
In geographic tongue, some areas of the tongue are white or yellow and rough, whereas others are red and smooth. The areas of discoloration move around over a period of weeks to years. The condition is usually painless, and no treatment is needed.
Sores and Bumps:
Sores on the tongue can be caused by allergic reactions, oral herpes simplex virus infection, canker sores, tuberculosis, bacterial infections, or early-stage syphilis. Sores can also be caused by allergies or other immune system disorders.
Although small bumps on both sides of the tongue are usually harmless, a bump on only one side may be cancerous. Unexplained red or white areas, sores, or lumps (particularly when hard) on the tongue—especially if painless—may be signs of cancer and should be examined by a doctor or dentist (see Mouth Growths: Types of Oral Cancer). Most oral cancers grow on the sides of the tongue or on the floor of the mouth. Cancer almost never appears on the top of the tongue, except when the cancer occurs after untreated syphilis.
Tongue discomfort can result from irritation by certain foods, especially acidic ones (for example, pineapple), or by certain ingredients in toothpaste, mouthwash, candy, or gum. Some drugs can cause tongue discomfort, as can injury and infection. A common infection causing tongue discomfort is thrush (candidiasis---see Fungal Skin Infections: Candidiasis), in which an overgrowth of fungi forms a white film that covers the tongue. Intense pain of the entire mouth can be caused by burning mouth syndrome.
Usually, it is a process of elimination to find out just what is causing the discomfort. Tongue discomfort not caused by an infection is usually treated by eliminating the cause. For example, the person may try changing brands of toothpaste, stop eating irritating foods, or have a sharp or broken tooth repaired by a dentist. Warm salt-water rinses may help. Thrush can be treated with an antifungal drug, such as nystatin or fluconazole.
Last full review/revision October 2006 by Robert B. Cohen, DMD