What does this mean?
The top of the tongue is covered with short, slender papillae known as filiform papillae; they are what give the surface its matt, slightly velvety look. In geographic tongue these papillae are temporarily lost in certain areas. Where they are missing, the network of blood vessels underneath lies close to the surface, so the tissue looks red and shiny. Around the edge, the papillae bunch together and form a whitish, slightly raised border. A red island sitting inside a white rim is what produces the look of landmasses on a map.
What sets this appearance apart from similar ones is that it moves. The position and shape of the patches change within days; an area sitting on the right edge of your tongue one morning may turn up in the middle, or somewhere else entirely, a week later. Permanent white patches and scars in the mouth stay where they are, whereas the pattern of geographic tongue wanders. Because the surface is lost and rebuilt, this wandering is the expected course.
For most people geographic tongue is painless and is noticed by chance in the mirror. In some people the bare areas can burn when they meet spicy, acidic or very salty food, or fizzy drinks. Deep fissures on the top of the tongue may go with this appearance in the same person. It has not been shown to be contagious. Even so, if there is a single patch whose border never changes, that patch should be assessed separately.
No single cause of geographic tongue has been established; several factors that affect the renewal cycle of the surface may be acting together. The headings below bring together the conditions that most often accompany this appearance.
Likely causes
What helps at home?
- Keep a note for a few days of the foods that make it burn; chilli, vinegar, citrus fruit and very salty snacks are the ones reported most often.
- Do not scrub your tongue with a brush or a scraper; the red areas are already thinned surface, and mechanical irritation makes the burning worse.
- While the discomfort lasts, leave aside mouthwashes that contain alcohol and mouth sprays heavy with peppermint oil.
- Photograph the area you can see, a few days apart; whether the shape has changed makes it easier for your dentist to assess.
- If the same red or white patch has stayed in exactly the same place for two weeks without moving.
- If there is an ulcer that will not heal, a hardened area or a lump on the patch.
- If the burning carries on all day regardless of eating and breaks your sleep.
- If an area has appeared that bleeds when it is touched.
- If a temperature, widespread redness inside the mouth and difficulty swallowing have joined the picture.
Frequently asked questions
- Is geographic tongue contagious?
- It has not been shown to be contagious. There is no evidence that it passes on through kissing, drinking from the same glass or sharing cutlery. When more than one person in a family has it, that is put down to a shared tendency rather than to catching it.
- Can this appearance be an early warning of cancer?
- In its known course, geographic tongue is not described as a condition that turns into malignant tissue. But if there is a single patch on the tongue that lasts longer than two weeks and never moves, or an ulcer that will not heal, that is a separate finding and needs to be seen by a dentist.
- Does it go away, and is there a treatment?
- In most people the areas fade on their own and reappear somewhere else after a while; this up-and-down course can go on for years. No treatment has been described that removes the appearance altogether. If the trouble is burning, cutting back on irritating foods and the supportive measures your dentist thinks appropriate may bring relief.
This content is for general information and does not replace an in-person examination. Symptoms overlap between conditions, and a diagnosis can only be made clinically.