Black hair tongue, also known as lingua villosa nigra, is a condition distinguished by the tongue's black and hairy appearance. This discoloration stems from the accumulation of bacteria and debris on the surface of the tongue. A person may experience an altered sense of taste and bad breath as a result.
Black hair tongue is a relatively harmless condition and resolves itself within a few weeks or months. It can be brought about by various factors, including smoking, excessive consumption of coffee or tea, or poor oral hygiene. Historically, treatments for black hair tongue included scraping the tongue or using antiseptic mouthwashes.