Black hairy tongue is a temporary, harmless oral condition that gives the tongue a dark, furry appearance. The distinct look usually results from a buildup of dead skin cells on the many tiny projections (papillae) on the surface of the tongue that contain taste buds. These papillae, which are longer than normal, can easily trap and be stained by bacteria, yeast, tobacco, food or other substances.

Although black hairy tongue may look alarming, typically it doesn't cause any health problems, and it's usually painless. Black hairy tongue usually resolves by eliminating possible causes or contributing factors and practicing good oral hygiene.

Signs and symptoms of black hairy tongue include:

• Black discoloration of the tongue, although the color may be brown, tan, green, yellow or white
• A hairy or furry appearance of the tongue
• Altered taste or metallic taste in your mouth
• Bad breath (halitosis)
• Gagging or tickling sensation, if the overgrowth of the papillae is excessive

When to see a doctor

Though unattractive, black hairy tongue is usually a temporary, harmless condition.

See your doctor if:

• You're concerned about the appearance of your tongue
• Black hairy tongue persists despite brushing your teeth and tongue twice daily

Black hairy tongue typically results when projections on the tongue called papillae grow longer because they don't shed dead skin cells like normal. This makes the tongue look hairy. Debris, bacteria or other organisms can collect on the papillae and result in discoloration.

Although the cause of black hairy tongue can't always be determined, possible causes or contributing factors include:

• Changes in the normal bacteria or yeast content of the mouth after antibiotic use
• Poor oral hygiene
• Dry mouth (xerostomia)
• Regular use of mouthwashes containing irritating oxidizing agents, such as peroxide
• Tobacco use
• Drinking excessive amounts of coffee or black tea
• Excessive alcohol use
• Eating a soft diet that doesn't help to rub dead skin cells from your tongue

Diagnosis of black hairy tongue is based on appearance and possible causes or contributing factors. It also includes eliminating other conditions that may cause a similar appearance to the tongue, such as:

• Normal variations in tongue color (pigment)
• Foods or medications that have stained the tongue
• Fungal or viral infections
• Oral lesions that occur on the tongue, such as oral hairy leukoplakia
• Blackened tongue (pseudo-black hairy tongue) from using products containing bismuth, such as Pepto-Bismol

Black hairy tongue typically doesn't require medical treatment. Though unattractive, it's a temporary, harmless condition.

Practicing good oral hygiene and eliminating factors that may contribute to the condition — such as avoiding tobacco use or irritating mouthwashes — help resolve black hairy tongue. Be sure to talk to your doctor or dentist before stopping a prescribed medication.

To practice good oral health and to remove the tongue discoloration:

• Brush your tongue. Give your tongue a gentle brushing whenever you brush your teeth to remove dead cells, bacteria and food debris. Use a soft-bristled toothbrush or a flexible tongue scraper.
• Brush after eating. Brush your teeth at least twice a day and ideally after every meal, using fluoride toothpaste.
• Floss at least once a day. Proper flossing removes food particles and plaque from between your teeth.
• Visit your dentist regularly. Get professional teeth cleanings and regular oral exams, which can help your dentist prevent problems or spot them early. Your dentist can recommend a schedule for you.
• Maintain good nutrition. Drink plenty of water and eat a balanced diet that contains fresh fruits and vegetables.

Here's information to help you get ready for your appointment, and to know what to expect from your doctor or dentist.

What you can do

Before your appointment, make a list of:

• Any symptoms you're experiencing, including any that may seem unrelated to the reason for your appointment
• All prescribed medications, vitamins, herbs, other supplements and over-the-counter medications you're taking, including the dosages
• Questions to ask your doctor or dentist

Some basic questions to ask your doctor or dentist may include:

• What is likely causing my symptoms?
• What is the best course of action?
• Are there any restrictions that I need to follow?
• What kind of follow-up, if any, should I expect?

Don't hesitate to ask any other questions during your appointment.

What to expect from your doctor or dentist

Your doctor or dentist may ask you questions about your symptoms and oral care practices, including:

• When did you first notice the symptoms?
• Are your symptoms occasional or continuous?
• How often do you brush your teeth or clean your dentures?
• How often do you floss?
• What kind of mouthwash do you use?
• How much coffee or tea do you drink?
• Do you use tobacco products?
• What medications, herbal products or other supplements do you take?
• Do you breathe through your mouth?
• Have you had any recent infections or illnesses?