What could cause my tongue to turn dark brown and fuzzy?

Q. The top of my tongue has taken on a dark brown color and a fuzzy look. Certain foods taste different, but otherwise I feel fine. What might cause this?

A. It's likely that you have a condition called black hairy tongue. But it's not as bad as it sounds.

The top of the tongue is covered with millions of papillae. It's like grass blades on a lawn. But they are so small you usually can't see them with the naked eye.

The papillae remain very short because they keep getting knocked off the tongue by chewing and good oral care. New ones grow in to replace the ones that get knocked off.

But if oral conditions change, the papillae can remain in place and continue to grow. They can grow to twice the usual length. The long papillae can trap food particles and bacteria. This can cause the dark color and fuzzy look you've noticed.

Although black hairy tongue is not pretty, it's not serious, either. In fact, you should be able to correct the problem yourself.

• Keep your saliva flowing. Drink plenty of water. Avoid letting you mouth get too dry.
• Take antibiotics only when needed. Antibiotics change the type of bacteria in your mouth and let a yeast infection take hold.
• Practice good oral care. Brush your teeth and tongue after each meal. Use a soft-bristle toothbrush on your tongue. Floss at least once per day.

If all goes well, you should see a clear improvement within two or three weeks. But if it doesn't get better, ask your dentist or doctor to take a look.

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