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Disease Profile

Black hairy tongue

Prevalence estimates on Rare Medical Network websites are calculated based on data available from numerous sources, including US and European government statistics, the NIH, Orphanet, and published epidemiologic studies. Rare disease population data is recognized to be highly variable, and based on a wide variety of source data and methodologies, so the prevalence data on this site should be assumed to be estimated and cannot be considered to be absolutely correct.


US Estimated

Europe Estimated

Age of onset





Autosomal dominant A pathogenic variant in only one gene copy in each cell is sufficient to cause an autosomal dominant disease.


Autosomal recessive Pathogenic variants in both copies of each gene of the chromosome are needed to cause an autosomal recessive disease and observe the mutant phenotype.


dominant X-linked dominant inheritance, sometimes referred to as X-linked dominance, is a mode of genetic inheritance by which a dominant gene is carried on the X chromosome.


recessive Pathogenic variants in both copies of a gene on the X chromosome cause an X-linked recessive disorder.


Mitochondrial or multigenic Mitochondrial genetic disorders can be caused by changes (mutations) in either the mitochondrial DNA or nuclear DNA that lead to dysfunction of the mitochondria and inadequate production of energy.


Multigenic or multifactor Inheritance involving many factors, of which at least one is genetic but none is of overwhelming importance, as in the causation of a disease by multiple genetic and environmental factors.


Not applicable


Other names (AKA)

Hairy tongue; Lingua villosa


Black hairy tongue is a relatively common condition in which the the central top portion of the tongue presents with an abnormal coloring and coating. Although the abnormal coating is typically black in color, brown, yellow, and green discoloration have been described. Individuals with black hairy tongue usually do not have symptoms, although occasionally there may be a burning, gagging, or tickling sensation. Halitosis (bad breath) or abnormal taste may additionally be present. Black hairy tongue can occur at any age, but the incidence increases with age. Black hairy tongue occurs due to a lack of stimulation on the top of the tongue resulting in a buildup of a protein known as keratin. This buildup can become quite long, giving it a hair-like appearance. Though black hairy tongue can present at any point, certain factors increase one's risk, such as poor oral hygiene, use of medications (particularly antibiotics), tobacco use, therapeutic radiation, and certain illnesses. Treatment varies depending on complexity; however, many cases can easily be resolved with brushing the tongue with a toothbrush or using a tongue scraper.[1][2][3]


The exact cause of black hairy tongue is unknown; however, it is thought to be related to ineffective shedding of the outermost portion of the central top area of the tongue. This leads to accumulation of layers of tissue and a protein called keratin. The accumulations take on a hair-like appearance and can reach a length of 12-18 mm. While black hairy tongue can occur at any point, certain lifestyle factors can increase the risk such as use of tobacco and alcohol, dehydration, and poor oral hygiene. Low saliva production, trigeminal neuralgia and cranial radiation therapy have additionally been found to increase the risk for black hairy tongue to develop.[3]


Although black hairy tongue normally resolves on its own, patients are encouraged to avoid the factors that have been shown to bring about hairy tongue. Treatment usually involves gentle cleaning of the tongue with a soft toothbrush. Medication is rarely prescribed for hairy tongue; however, in severe cases, antifungals, retinoids or mouthwashes may be used. If treatment fails, the affected portion of the tongue called the papillae (finger-like projections) may be clipped or removed using techniques such as carbon dioxide laser burning or electrodesiccation (a procedure in which an electrical current is used to seal of the affected area).[4][1]

Learn more

These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

Where to Start

In-Depth Information

  • Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
  • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
  • PubMed is a searchable database of medical literature and lists journal articles that discuss Black hairy tongue. Click on the link to view a sample search on this topic.


  1. Gary L Stafford. Hairy Tongue. Medscape. October 22, 2015; https://emedicine.medscape.com/article/1075886-overview.
  2. L Radfar and the AAOM Web Writing Group. Hairy Tongue. American Academy of Oral Medicine. May 13, 2015; https://www.aaom.com/hairy-tongue.
  3. Grigoriy E Gurvits, Amy Tan. Black hairy tongue syndrome. World Journal of Gastroenterology. August 21, 2014; 20(31):10845-10850. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4138463/.
  4. Mcgrath EE, Bardsley P, Basran G. Black hairy tongue: What is your call?. Canadian Medical Association Journal. April 2008;

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