“Hairy tongue” is a term used to describe an abnormal coating on the top surface of the tongue. It is a common, temporary, and harmless condition that affects about 13% of the population at one point or another.
The tongue is covered with conical-shaped projections called filiform papillae that are normally approximately 1 millimeter in length. In severe cases of hairy tongue, the papillae can become long, giving a hair-like appearance to the top of the tongue.
Normally, the papillae shed regularly, but when they don’t properly shed, food, bacteria, and yeast can accumulate in the hair-like mesh, resulting in the surface of the tongue appearing to be different colors.
Black hairy tongue is caused by certain types of bacteria and yeast. Hairy tongue may also appear brown, white, yellow, green, or even pink.
The way to get rid of black hairy tongue is by practicing good oral hygiene. Using a toothbrush or tongue scraper can eliminate the buildup on the tongue. Use of a solution containing 3% hydrogen peroxide or baking soda may help remove the buildup.
Other measures that may help get rid of black hairy tongue include:
- Stopping any medications that may cause or contribute to the problem
- Never stop taking a prescribed medication without first talking to your doctor
- Antiseptic mouthwash
- Topical antifungal agent for oral Candida albicans if present
- Topical retinoids
For people who have a persistent coating on the tongue that does not resolve with simple measures, trimming papillae by carbon dioxide laser burning and electrodessication may be recommended.
What Are Symptoms of Black Hairy Tongue?
The main symptom of black hairy tongue is the unsightly appearance of the tongue. The papillae that are normally about 1 millimeter in length may grow up to 18 mm in length and have a “hairy” appearance. The back surface of the tongue is usually affected, and the tip and sides of the tongue are usually normal in appearance.
A black hairy tongue is often not accompanied by other symptoms. When additional symptoms do occur, they may include:
- A burning sensation on the tongue
- A gagging or a tickling sensation in the roof of the mouth during swallowing
- Nausea
- Bad breath (halitosis)
- Abnormal taste
What Causes Black Hairy Tongue?
Black hairy tongue is caused by a lack of stimulation or abrasion to the top of the tongue which results in the surface of the tongue not shedding properly. Causes of this lack of stimulation include:
- Poor oral hygiene
- Use of certain medications including penicillin, erythromycin, tetracycline, doxycycline, lansoprazole, olanzapine, bismuth, erlotinib, and linezolid
- Smoking or chewing tobacco
- Colored beverages, including coffee and tea
- Drinking alcohol
- Chlorhexidine or peroxidase-containing mouthwash
- Dehydration
- Dry mouth
- Radiation therapy to the head and neck area
- Cocaine use
Black hairy tongue may also develop in people who have no teeth because a soft food diet does not help with the normal shedding of the papillae.
How Is Black Hairy Tongue Diagnosed?
Most of the time, dentists or doctors can diagnose black hairy tongue by appearance alone and no additional testing is needed, however, tests may be done to determine the cause, such as:
- Swabs for bacterial culture
- Fungal scrapings
- Tongue biopsy
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