A sore tongue is usually harmless. The coating develops because food remains, cells, or bacteria are deposited on the back of the tongue. This natural coating on the tongue disappears when chewing solid food or brushing your teeth. However, if the sore tongue is permanently coated, this can indicate illness. Read about the causes of sore tongues and how to prevent and treat them.
Covered tongue: Causes and forms
The surface of the tongue consists of a mucous membrane covered by various types of papillae. Dead cell parts, food remnants, and bacteria always stick to this rough surface. They form a natural, fine coating on the tongue, which disappears when you chew solid food or brush your teeth.
However, if the coating on the tongue is persistent, this may be due to inadequate oral hygiene or disease. The color of the plaque often gives an indication of what is behind it.
White coating of the tongue: Causes
In a white-sore tongue, the coating typically consists of dead cells, microorganisms and food remain that settle on the rough surface of the tongue.
The white coating can also be more common in the following diseases:
- Cold and fever
- Mouth sores: In case of an infection with the fungus Candida albicans, white coatings appear in the entire mouth, which can be easily removed. Underneath, a slightly bleeding, reddened mucous membrane then appears.
- Digestive disorders: Gastritis and other diseases of the digestive organs (e.g. of the pancreas) can also be the reason for a whitish coating on the tongue.
- Leukoplakia: Whitish, solid coatings on the base or edge of the tongue indicate leukoplakia. The mucous membrane produces more corneous cells, which can be a precursor of cancer. Normally, the coatings are not only on the tongue, but also on other mucous membranes.
- Bowen’s disease: Also a precursor of cancer. Typical are reddish discolored mucous membranes, including those of the tongue.
- Lichen ruber planus: This skin disease affects the mucous membranes of the mouth, among other things. However, it hardly ever shows up on the surface of the tongue. Only the underside of the tongue and the inner sides of the cheeks are covered with white coatings.
- Iron deficiency anemia: Here the tongue looks remarkably pale.
- Typhoid fever: The typhoid tongue has a grayish-white coating in the middle. The affected areas are separated from their surroundings in red.
Yellowish coating of the tongue: Causes
Yellow tongue coating can indicate diseases of the digestive organs. Especially jaundice (icterus) and biliary diseases can cause a yellowish sore tongue.
Red coating of the tongue: Causes
A healthy tongue is slightly pink colored. In some infectious diseases, however, the tongue presents itself strongly reddened, for example in the case of:
- Scarlet fever: This streptococcal infection is associated with fever, chills, sore throat, and a characteristic skin rash. The sore tongue is initially white, later it turns red with clearly enlarged papillae – this is called a “raspberry tongue”.
- Vitamin B12 deficiency: This deficiency can lead to pernicious anemia. This anemia is manifested, among other things, by a smooth, red, inflamed tongue and tongue burning (Hunter’s Glossitis).
- Inflammation of the tongue (glossitis): The tongue can become inflamed due to bacterial or viral infections, an unbalanced diet, systemic diseases, and regular alcohol or nicotine consumption. One sign of this is a reddish coating on the tongue.
- Sjögren’s syndrome: This autoimmune disease destroys the salivary glands. A dry mouth and a shiny red “varnished tongue” are typical symptoms. Women are particularly affected.
- Kawaski Syndrome: Similar to scarlet fever, this disease manifests itself through fever and a red raspberry tongue.
Brown coating on the tongue: Causes
A brown coating on the tongue can occur, for example:
- the taking of certain medicines
- Kidney weakness (According to traditional Chinese medicine, a swollen, brown sore tongue can indicate kidney weakness)
- the frequent, intensive use of mouthwash with chlorhexidine
Black coating of the tongue: Causes
Common causes for a gray-black discolored tongue are
- regular consumption of tobacco, mouthwash, coffee, and certain coloring foods
- increased growth of special papillae of the tongue: The enlarged papillae optically appear as if the tongue is covered with fine hairs. The tongue can then change its color from brown to black due to food influences (black hair tongue = Lingua villosa nigra). The phenomenon is harmless. Men are more frequently affected than women.
Other causes of tongue coating
There are many other factors that can cause sore tongues of varying intensity and color, for example:
- Poisons / Metals
Even harmless deviations in the shape and texture of the tongue can promote tongue coating, including:
- Lingua geographica (map tongue): Here the tongue temporarily loses certain papillae. This results in whitish and reddish areas on the surface of the tongue that resemble a map.
- Lingua plicata (wrinkled tongue): Some people have – hereditary – severe wrinkles in the tongue. These provide an ideal refuge for bacteria. The result is an increased coating on the tongue.
- Glossitis mediana rhombica: A part of the middle and back surface of the tongue is not covered by papillae. White or reddish coating of the tongue is often found there.
Special case of tongue burning
Significantly more women than men suffer from burning mouth syndrome. The tip of the tongue and the lower edge of the tongue are particularly affected, and sometimes the entire oral cavity. However, the mucous membrane itself usually remains unchanged. Burning of the tongue can occur daily or only occasionally. In the evening it usually gets stronger.
The causes of the burning tongue are manifold. They range from psychological triggers to ill-fitting dentures to systemic diseases.
Sore tongue: Diagnosis
A sore tongue is not only associated with a furry feeling but also often leads to bad breath. Although this is unpleasant, it is not a reason for a visit to the doctor. Only if additional complaints such as tongue burning, fever, or a general feeling of illness occur or if the coating of the tongue changes significantly, you should consult a doctor (family doctor or dentist).
The physician will first ask for your medical history during the initial consultation (anamnesis). He will, for example, have your symptoms described in detail, ask how long they have existed and whether you are aware of any underlying diseases.
The interview is followed by physical examinations to identify possible underlying diseases. The doctor will thoroughly examine the sore tongue, the oral mucosa, and the teeth. Your dentist should rule out gum disease and dental problems.
Usually, a smear is taken from the coating of the tongue and examined in the laboratory for possible infections with bacteria, viruses, or the fungus Candida albicans.
Sometimes further examinations are necessary to find the cause of the sore tongues. These include blood sampling, gastroscopy, or imaging procedures such as X-rays or magnetic resonance imaging (MRI).
Sore tongue: treatment
The treatment of a sore tongue depends on its cause. For example, infections with fungi, bacteria, or viruses can often be treated well with special medications – antifungals (antifungals), antibiotics, or antivirals.
If problems with the teeth or gums are responsible for the plaque on the tongue, the dentist should take over the treatment.
What you can do yourself!
There is a lot you can do yourself against harmless tongue plaque without a serious cause. Special tongue hygiene is particularly important. The rough surface of the tongue is an ideal breeding ground for bacteria, fungi, and viruses. When brushing your teeth, you should therefore not only brush your teeth but also your tongue. Suitable acids are for example:
- Tongue cleaner with brush and scraper. Brush the tongue several times with the brush to loosen the coating. Then remove it with the scraper. Rinse the mouth thoroughly with water or a mouthwash.
- Tablespoon or toothbrush: If you do not have a tongue cleaner at hand, you can use a tablespoon. Stroke the edge of the hollow side several times over the back of the tongue. This way you can remove the plaque. If necessary, you can also use a toothbrush. Afterwards you should wash it out very thoroughly.
- Disinfection: The use of disinfecting mouthwash after brushing your teeth reduces the number of germs in your mouth. You can buy such mouthwash ready to use or make it yourself from sage, myrrh, and thyme, for example. However, the active plant ingredients can cause the tongue to turn brownish.
In addition to tongue care, chewing helps to prevent deposits on the tongue: eat as much solid food as possible (e.g. raw vegetables), because chewing hard crusts and crunchy vegetables remove the deposits by itself – the most natural way to avoid a coated tongue.