My doctor has diagnosed me with fuzzy tongue disease. What is it, what causes it, and how do I get rid of it?

S.

This is better known as "black (or brown) hairy tongue," or simply "hairy tongue." This is a descriptive name: Individuals with hairy tongue look like they have been licking Furbies. (That's a children's toy, for you folks out there who don't have kids!)

So ... why does your tongue look hairy? Keratin. Keratin is one of the chief protein constituents of skin, hair, toenails and fingernails. Keratin is found in all epithelial tissues (i.e., not just skin, but also the mucous membranes that line your nose, mouth, tongue, esophagus, stomach and so forth). Hairy tongue is due to an accumulation of keratin within the taste buds on the top surface of the tongue.

There are a variety of possible causes for this odd problem: heavy tobacco use is (arguably) one of the most common causes. Other possibilities include poor oral hygiene, medications (such as antibiotics or antacids), oxidizing mouthwashes (some folks rinse with hydrogen peroxide!) and a history of radiation therapy to the oral cavity.

Treatment for this condition is optional, since hairy tongue has no serious health consequences. If you are offended by the appearance of your tongue, you should try to limit exposure to the substances mentioned above, practice excellent oral hygiene and regularly "clean" the top surface of your tongue with a toothbrush or tongue scraper.

You need to be certain that your doctor is talking about "hairy tongue" and not "hairy leukoplakia," which is a much different problem and has a much different appearance. In this condition, there are white plaques at the lateral borders of the tongue that cannot be scraped off. These white plaques may also involve the top surface of the tongue.

The appearance of hairy leukoplakia is reminiscent of a yeast infection (thrush), and confusion may result since the yeast that causes thrush (candida) often colonizes these white patches. Unfortunately, hairy leukoplakia is NOT thrush. Hairy leukoplakia may be due to an Epstein-Barr virus infection. Its primary significance is the fact that it occurs in immunocompromised individuals: organ transplant patients, leukemia patients and individuals infected with HIV. In fact, in HIV-positive individuals, hairy leukoplakia is thought to foreshadow the imminent development of AIDS.

So ... I am not trying to spook you, but you probably ought to ask your doctor to clarify this diagnosis of "fuzzy tongue disease."