Merck Manual

Please confirm that you are a health care professional

honeypot link

Tongue Discoloration and Other Changes


Bernard J. Hennessy

, DDS, Texas A&M University, College of Dentistry

Reviewed/Revised May 2022 | Modified Sep 2022
Topic Resources

Tongue color changes

The papillary surface (dorsum) of the tongue may become discolored by smoking or chewing tobacco, consuming certain foods or vitamins, or by surface growth of pigmented bacteria.

Black discoloration on the dorsum may be due to oral bismuth preparations. Brushing the tongue with a toothbrush or scraping it with a tongue scraper may remove such discoloration.

Blue-black discoloration, focal, small, and unchanging, on the ventral surface, may be an amalgam tattoo.

Magenta tongue suggests vitamin B12 deficiency.

Tongue surface changes

The most common tongue surface changes, all 3 benign, are

  • Geographic tongue (benign migratory glossitis, or erythema migrans)

  • Fissured tongue (often associated with geographic tongue)

  • Hairy tongue

In geographic tongue, areas of the tongue are red and smooth (due to atrophy of filiform papilla) and are often surrounded by a slightly elevated yellow-white border. Other areas may be white or yellow and rough, representing psoriaform changes or coexisting psoriasis itself. The areas of discoloration can migrate 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 topical corticosteroid sometimes helps.

Tongue Surface Changes

Fissured tongue is an idiopathic condition usually occurring in about 5% of adults in the US (and in up to 30% of older adults). Deep grooves are located either along the midline or are distributed over the dorsum. Fissured tongue may occur with geographic tongue, Down syndrome Down Syndrome (Trisomy 21) Down syndrome is an abnormality of chromosome 21 that can cause intellectual disability, microcephaly, short stature, and characteristic facies. Diagnosis is suggested by physical anomalies... read more Down Syndrome (Trisomy 21) , or Melkersson-Rosenthal syndrome, a rare syndrome that also features facial palsy and granulomatous cheilitis.

Hairy tongue is due to accumulation of keratin on normal filiform papillae that gives the tongue a hairy appearance. Hairy tongue is caused by lack of mechanical stimulation to the tongue (eg, due to poor oral hygiene) with trapping of residual food debris among the papillae. Hairy tongue may also appear after a fever, antibiotic treatment, or with excessive use of peroxide mouthwash. It is common in heavy smokers. Hairy tongue should not be confused with hairy leukoplakia, which usually is associated with immunodeficiency (especially HIV infection Human Immunodeficiency Virus (HIV) Infection Human immunodeficiency virus (HIV) infection results from 1 of 2 similar retroviruses (HIV-1 and HIV-2) that destroy CD4+ lymphocytes and impair cell-mediated immunity, increasing risk of certain... read more Human Immunodeficiency Virus (HIV) Infection ) and caused by the Epstein-Barr virus. It appears as white, hairy-appearing patches on the side of the tongue.

Other tongue surface changes include tongue ulcers, whitish patches, and red patches.

Tongue ulcers may be herpetiform aphthous ulcers (ventral tongue surface) or be due to trauma from accidental biting or from rubbing against a fractured tooth or restoration.

Whitish patches on the tongue, similar to those sometimes found inside the cheeks, may be due to

Changes in the Mouth and Tongue

Red patches on the tongue may indicate

Drugs Mentioned In This Article

Drug Name Select Trade
ENDUR-ACIN, ENDUR-AMIDE, Niacor, Niaspan, NiaVasc, Nicomide-T, Slo-Niacin
NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
quiz link

Test your knowledge

Take a Quiz!