A black coating on the tongue, called black hairy tongue, may be caused by a number of things including changes in bacteria in the mouth, poor oral hygiene and dry mouth, explains Mayo Clinic. Other causes are medications containing bismuth, tobacco use and eating a soft diet.
Those who experience black hairy tongue may panic, but this is a harmless condition, according to Mayo Clinic. In most cases, treatment includes changing behaviors, such as improving oral hygiene or drinking more water to eliminate dry mouth. In most cases, this is a temporary condition and should go away without medical intervention. If the person is concerned about the appearance of his tongue or if the black tongue does not disappear after improving oral hygiene, seeing a doctor or dentist is recommended.
In order to improve oral health and eliminate black hairy tongue, there are certain things that a person should do, states Mayo Clinic. Brushing the tongue with a soft toothbrush or using a tongue scraper, for example, is recommended. It is also important to brush the teeth and tongue following eating and drinking, and if this isn't possible, rinsing with water may help. Flossing the teeth and visiting the dentist regularly is also important in improving oral health and eliminating a black tongue.