According to the National Organization for Rare Disorders, Inc. Black Tongue is also known as Black Hairy Tongue or in “doctorese” “lingua nigra”. It is characterized by a blackish or brownish discoloration or staining of the filiform papillae and may include an elongation of the papillae. Such changes often begin at the back (posterior) of the tongue and work their way forward. But never involve the undersurface.
These changes often result in the growth and discoloration of the papillae and may begin with the circumvallate papillae at the back of the tongue.
Hairy tongue is thought to be the result of inadequate “shedding” of the outermost layer of the papillae. The color may be the result of pigment-producing bacteria or fungi normally present in the mouth and an abnormal accumulation of pigment residues, keratin and other debris on the tongue. Keratin is a type of protein that makes up skin and nails and hair.
Doctors are not positive what causes black hairy tongue but they know that several factors contribute to you getting it. The easiest way to turn your tongue black is to chew a “Pepto-Bismol” tablet. It will almost always turn your tongue black!
Obviously that will not make the papillae longer, however. Other contributing factors noted by doctors are smoking, antibiotic medications that allow other fungi to proliferate, certain mouthwashes, chewing tobacco, excessive alcohol use and poor oral hygiene.
Smoking has a high correlation with Black tongue so I would think that this would be the first thing a doctor would tell this particular patient. Think about all the smokers you know with brown teeth! Is it also possible it will turn your tongue and lungs brown? The brown tongue above almost looks like a smoker’s teeth. The black tongue, however, may be more likely caused by Pepto Bismol, or perhaps some other medication. Activated charcoal and iron supplements could possibly cause a black tongue or licorice candy, as could simple things like eating blueberries! Check all your prescription medications and see if any of them list Black tongue as a possible side effect.
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