A temporary condition in which the tongue appears dark and furry.

Black hairy tongue usually is a harmless condition. It's caused by a buildup of dead skin cells on the tiny projections that contain taste buds. Possible causes include antibiotic use, tobacco use, eating a soft diet, poor cleaning of the mouth and tongue, dry mouth and other issues.

Symptoms include black color of the tongue, a furry or hairy look to the tongue, bad breath, and a metallic taste in the mouth. Sometimes the color of the tongue may be brown, green, yellow or white.

Black hairy tongue often clears up without medical treatment. Good mouth and tongue cleaning can help get rid of it. So can stopping things that may lead to the condition, for example, not using tobacco.