There is such a thing as black tongue “hair.” It’s a rare condition called black hairy tongue or lingua villosa nigra.
According to a CNN report, the so-called hair in the tongue discoloration isn’t actually hair at all. The condition occurs when filiform papillae, small nubs on the tongue, grow longer than their typical length of less than a millimeter. In cases of the unusual black colored tongue, the papillae grow as long as 12 and 18 millimeters, and they eventually turn black.
A possible reason for the black color is that the longer papillae trap tiny pieces of food, which allows for bacteria and other microbes to overgrow inside the mouth, and that ends up causing the shocking coloration. While sometimes black hairy tongue occurs merely as a side effect from drugs and is harmless, other times it is a health hazard linked to smoking, bad oral hygiene, or irritating mouthwashes, or a sign of certain medical conditions.
Dr. Yasir Hamad, an assistant professor in the Department of Medicine at the Washington University School of Medicine in St. Louis, recently published the details of a rare case of black hair tongue in the New England Journal of Medicine.
According to Hamad, “It was the typical textbook case.” He added, “As scary as this looks, the good part is that it’s actually reversible.”
His patient, a 55-year-old woman, had taken minocycline, a broad-spectrum antibiotic, because her legs were crushed in a car accident, and doctors were treating her serious wounds to ensure she did not get an infection. Her symptoms started about a week later when she noticed not only a black colored tongue but also nausea and a gross taste in her mouth. After her doctors changed her medication, the woman’s tongue was back to normal within four weeks.
Hamad said people experiencing a blackened tongue should “check with your primary doctor, because some other conditions can resemble this.”
He also advised his colleagues in medicine that “A lot of things you can diagnose just from looking at the mouth. That’s the lesson: Don’t miss that part of the body when you’re examining the patient.”
Many doctors never see this condition outside of their textbooks in medical school. Hamad had practiced for 10 years before he saw a case like this in person. Scientists still do not have a great idea about why this condition sometimes occurs, but typically it is not too dangerous.