Black tongue is a condition that usually starts at the back of the tongue before progressing toward the front. It is characterized by a dark discoloration of the small thread-like elevations on the top surface of the tongue. The condition also elongates these threads, giving the affected part of the tongue a hairy appearance. Black tongue does not affect the underside of the tongue and is a harmless condition that goes away on its own in most cases. The Mayo Clinic lists the most likely cause as bacteria overgrowth in the mouth.
The Mayo Clinic states that the condition of black tongue can give the affected area a furry appearance. The affected area is also discolored, and although the name of the condition is black tongue, the color can also be yellow or brown.
Causes of Black Tongue
Other symptoms of black tongue include halitosis, which is a condition more commonly known as bad breath. It is characterized by an unpleasant or offensive scent in exhaled air. Another symptom of black tongue is an altered taste in the mouth that can taste metallic. For some people, black tongue can also cause a feeling of gagging.
- Other symptoms of black tongue include halitosis, which is a condition more commonly known as bad breath.
- For some people, black tongue can also cause a feeling of gagging.
The Mayo Clinic suggests that medical attention does not need to be sought for this condition unless the condition causes concern about the appearance of the tongue or if the condition lasts for more than ten days. The Georgia Department of Community Health suggests a number of ways to practice good oral health and to remove the discoloration 1. These methods include brushing teeth after every meal or at least twice per day, flossing, brushing the tongue with a soft toothbrush or flexible tongue scraper, and regular dental visits.
Causes of Black Tongue
Causes of Tongue Discoloration
Diseases and Disorders of the Tongue
Can Certain Foods Cause Geographic Tongue?
A Whitish Tongue With Bumps on the Back
Food Allergies and a Coated Tongue
What Causes a White Coating on the Tongue?
What Causes White Spots in the Throat?
Large, White Bumps on the Tongue
Hair Growing in the Mouth
- Georgia Department of Community Health
- Kim AM, Keenan BT, Jackson N, et al. Tongue fat and its relationship to obstructive sleep apnea. Sleep. 2014;37(10):1639–1648. Published 2014 Oct 1. doi:10.5665/sleep.4072
- Bartlett JA, van der Voort Maarschalk K. Understanding the oral mucosal absorption and resulting clinical pharmacokinetics of asenapine. AAPS PharmSciTech. 2012;13(4):1110–1115. doi:10.1208/s12249-012-9839-7
- National Organization for Rare Diseases. Tongue Cancer.
- Dotiwala AK, Samra NS. Anatomy, head and neck, tongue. [Updated 2019 Feb 8]. In: StatPearls. Treasure Island (FL): StatPearls Publishing; 2019 Jan.
- Moore KL and AF Dalley. Clinically Oriented Anatomy. Lippincott Williams & Wilkins, 4th edition, 1999, pp. 940-947.
- Stone M, et al. Structure and variability in human tongue muscle anatomy. Comput Methods Biomech Biomed Eng Imaging Vis. 2018;6(5):499–507. Published online 2016 Apr 8. doi:10.1080/21681163.2016.1162752
Doug Hewitt has been writing for over 20 years and has a Master of Arts from University of North Carolina-Greensboro. He authored the book "The Practical Guide to Weekend Parenting," which includes health and fitness hints for parents. He and his wife, Robin, are coauthors of the "Free College Resource Book."