A coated or white tongue occurs when the surface is colonised by bacteria or fungi, and dead cells become trapped between the small nodules on the tongue.
A coated tongue isn’t a disease and isn’t usually a sign of anything serious. It’s usually only temporary.
You can try gently brushing it with a tongue scraper and drinking plenty of water to help it improve.
However, sometimes a coated tongue can indicate an infection or more serious condition. You should see your GP for advice if:
- you’re concerned about changes to the appearance of your tongue
- your tongue hurts (read about the causes of tongue pain)
- your coated tongue persists for longer than two weeks
You can read on to learn more about the possible causes of a coated tongue, but don’t use this to diagnose yourself with a condition always leave that to your GP.
Note that in a minority of people, a coated tongue may never return to its normal colour or texture, even after treatment.
White Tongue Causes
White tongue is the result of an overgrowth and swelling of the fingerlike projections (papillae) on the surface of your tongue. The appearance of a white coating is caused by debris, bacteria and dead cells getting lodged between the enlarged and sometimes inflamed papillae.
Causes of papillae hypertrophy or inflammation include, for example:
- Poor oral hygiene
- Dry mouth
- Congenital heart disease in adults
- Smoking or other oral tobacco use
- Alcohol use
- Mouth breathing
- Low roughage diet eating mostly soft or mashed foods
- Mechanical irritation from sharp tooth edges or dental appliances
Examples of conditions associated with white patches or other discolorations of your tongue include:
- Use of certain medications, such as prolonged use of antibiotics that may bring on an oral yeast infection
- Oral thrush
- Geographic tongue
- Oral lichen planus
- Mouth cancer
- Tongue cancer
There are a number of things that can cause a whitish coating or white spots to develop on the tongue, including:
- Leukoplakia. This condition causes cells in the mouth to grow excessively. That, in turn, leads to the formation of white patches inside the mouth, including on the tongue. Although not dangerous on its own, leukoplakia can be a precursor to cancer. So it is important for your dentist to determine the cause of white patches on your tongue. Leukoplakia can develop when the tongue has been irritated, and it is often found in people who use tobacco products.
- Oral thrush. Also known as candidiasis, oral thrush is a yeast infection that develops inside the mouth. The condition results in white patches that are often cottage cheese-like in consistency on the surfaces of the mouth and tongue. Oral thrush is most commonly seen in infants and the elderly, especially denture wearers, or in people with weakened immune systems. People with diabetes and people taking inhaled steroids for asthma or lung disease can also get thrush. Oral thrush is more likely to occur after the use of antibiotics, which may kill the “good” bacteria in the mouth. Eating plain yogurt with live and active cultures may help restore the proper fauna in your mouth. Additionally, medications may be used to combat the infection.
- Oral lichen planus. If you have a network of raised white lines on your tongue that has a lace-like appearance, you may be suffering from orallichen planus. Doctors are often unable to determine the cause of this condition, which often resolves on its own. Practicing proper dental hygiene, avoiding tobacco, and limiting your intake of foods that cause irritation to your mouth may helpful.