Tongue Lesions: Types, Causes and When to Worry

What counts as a tongue lesion

"Lesion" simply means an abnormal area of tissue. On the tongue, doctors group lesions by how they look, because appearance narrows the cause quickly:

• Ulcers and sores: a break in the surface, usually painful, with a white, yellow or gray base.
• White lesions: patches or plaques. Some wipe off (thrush), some do not (leukoplakia, lichen planus, hairy leukoplakia).
• Red lesions: smooth red patches, red bumps or map-like areas.
• Lumps and bumps: raised growths such as fibromas, papillomas, mucoceles and cysts.
• Pigmented lesions: brown, black or blue spots, usually from blood vessels, medicines or harmless pigment.

The tongue heals fast. That is why the most useful rule is about time: a lesion caused by injury or a minor infection should clearly improve within about 2 weeks once the cause is removed.

Types of tongue lesions and their causes

Common, harmless causes

Injury. Biting your tongue, burning it on hot food, or rubbing it against a broken tooth, filling, brace wire or ill-fitting denture is the commonest cause of a sore on the side of the tongue. The sore lines up with the source. It heals within 2 weeks once the edge is smoothed or the appliance adjusted.

Canker sores. Aphthous stomatitis causes round, shallow ulcers with a red halo. They are very painful for their size and often appear on the underside or tip of the tongue. Triggers include minor injury, stress, hormonal changes and sodium lauryl sulfate in toothpaste. Frequent outbreaks can point to iron, folate or vitamin B12 deficiency, celiac disease or inflammatory bowel disease.

Lie bumps. Transient lingual papillitis is inflammation of one or a few taste buds (fungiform papillae). It causes tiny, tender red or white spots on the tip or top of the tongue that disappear in a day or two. An eruptive form spreads through families, mostly children, with fever.

Geographic tongue. Geographic tongue produces smooth red patches with slightly raised white borders that shift position over days, giving a map-like look. It affects 1 to 3 in 100 people, is not contagious or cancerous, and sometimes stings with spicy or acidic food.

Infections

• Oral thrush: oral thrush causes creamy white patches that can be scraped off, leaving a red, sometimes bleeding surface. It is common in babies, denture wearers, people using inhaled steroids, after antibiotics, and with diabetes or a weakened immune system.
• Herpes simplex: a first infection, usually in young children, causes many painful blisters and ulcers across the tongue, gums and lips with fever. Later outbreaks are usually cold sores on the lip, but they can occur inside the mouth.
• Hand, foot and mouth disease: small ulcers on the tongue and inside the cheeks, with spots on the palms and soles, mostly in children under 5.
• Syphilis: a painless, firm ulcer (chancre) can appear on the tongue after oral sex, followed weeks later by gray-white "mucous patches".
• Oral hairy leukoplakia: white, ridged "corrugated" patches on the sides of the tongue that do not rub off. It is caused by Epstein-Barr virus and is a sign of a weakened immune system, especially HIV.

White lesions that do not wipe off

A white patch that stays put after you gently wipe it with gauze is called a non-wipeable white lesion. The main causes are:

• Frictional keratosis: thickened skin from chronic rubbing or chewing. It fades once the rubbing stops.
• Oral lichen planus: lacy white lines (Wickham striae), usually on both cheeks and sometimes the tongue. The erosive form is red and painful.
• Leukoplakia: a white patch with no other explanation. Most are benign, but some contain abnormal (dysplastic) cells, so it is biopsied and monitored.

Precancer and cancer

Oral cancer of the tongue is most often a squamous cell carcinoma on the side (lateral border) or underside of the tongue. Early signs are subtle: a persistent ulcer with raised, firm edges, a red or red-and-white patch, or a lump. Pain often comes late. Ear pain on the same side, a lump in the neck, or numbness can develop as it grows. The main risk factors are smoking or chewing tobacco, heavy alcohol use, betel quid and older age. Cancers at the base of the tongue are increasingly linked to HPV and can occur in non-smokers.

Other causes

• Medicines: some chemotherapy drugs, methotrexate, nicorandil and NSAIDs cause ulcers. Antibiotics and inhaled steroids can trigger thrush.
• Nutritional deficiencies: iron, B12 and folate deficiency cause a smooth, sore, red tongue (atrophic glossitis) as well as ulcers.
• Autoimmune and inflammatory disease: lupus, Behçet's disease, Crohn's disease and celiac disease can all produce recurrent mouth ulcers.
• Benign growths: a fibroma (firm, smooth, pink bump from repeated biting), a squamous papilloma (cauliflower-like bump from HPV) or a mucocele (soft, bluish fluid bubble, usually on the underside or lip).

Lesions on the side of the tongue

The side of the tongue is where most bite injuries, denture and tooth rubbing, hairy leukoplakia and tongue cancers occur. That overlap is why sores on the edge of the tongue cause so much worry. Clues that favor a harmless cause:

• it matches a sharp tooth, filling or brace
• it is painful from the start and improves quickly once the edge is smoothed
• it has soft edges and a clean yellow base

Clues that need a prompt check:

• it is painless or only mildly sore, yet persists beyond 2 to 3 weeks
• it feels firm or hard at its edges or base
• it has a red, speckled or mixed red-and-white surface
• you smoke, drink heavily, or are over 40

White lesions on top of the tongue

A white coating across the top of the tongue is usually a buildup of bacteria, food debris and dead cells trapped in the papillae, from dehydration, mouth breathing, smoking or a dry mouth. It brushes off and is not a lesion. Patches that form distinct areas are more meaningful: thrush wipes off, geographic tongue moves around, and leukoplakia and lichen planus stay fixed. A painful white tongue lesion that is round with a red rim is almost always a canker sore. A white coating with a burning feeling after antibiotics or steroid inhaler use suggests thrush.

Is a lesion on the tongue a cause for concern?

Most are not. The features that make a dentist or doctor look closer are:

1. Duration: present more than 2 to 3 weeks without healing.
2. Texture: hard, raised or rolled edges, or a lesion fixed to the deeper tissue.
3. Color: red (erythroplakia) or speckled red-and-white patches carry the highest risk.
4. Location: side or underside of the tongue, or floor of the mouth.
5. Associated signs: bleeding without injury, numbness, trouble moving the tongue, ear pain, or a firm neck lump.
6. Risk factors: tobacco in any form, heavy alcohol use, HIV or other immune suppression.

How doctors diagnose tongue lesions

A dentist is often the best first person to see, because they examine the mouth routinely. They or your doctor will:

• ask how long it has been there, whether it hurts, whether it has happened before, and about tobacco, alcohol, medicines and other symptoms
• look at and feel the lesion, check your teeth and dental work, and feel the neck for lymph nodes
• try to wipe off any white patch

Tests depend on the findings:

• Swab: for Candida or herpes virus.
• Blood tests: a blood count, iron studies, B12 and folate, and celiac antibodies for recurrent ulcers. HIV or syphilis testing when relevant.
• Biopsy: a small sample taken under local anesthetic. This is the only way to confirm or rule out dysplasia or cancer, and is advised for any lesion that persists after the likely cause has been removed.
• Imaging: CT, MRI or ultrasound of the neck if cancer is found.

Treatment and home care

Treatment targets the cause.

Home care for minor sores

• Rinse with warm salt water (half a teaspoon of salt in a cup of water) several times a day.
• Avoid spicy, acidic, salty and crunchy foods until it heals.
• Use a toothpaste free of sodium lauryl sulfate if you get frequent canker sores.
• Over-the-counter numbing gels with benzocaine or protective pastes can ease pain. Do not use benzocaine products in children under 2.
• Acetaminophen (paracetamol) or ibuprofen can help. Follow the label dose.
• Ask a dentist to smooth a sharp tooth or adjust a denture or brace.

Medical treatment

• Canker sores: prescription steroid gels or rinses, and treatment of any deficiency found.
• Thrush: antifungal drops, gels or lozenges, or tablets for more severe cases. Denture wearers need to clean and soak dentures and remove them overnight.
• Herpes: antivirals work best if started early. Children with a painful first infection mainly need fluids and pain relief.
• Lichen planus: steroid gels or rinses, and regular check-ups because of a small long-term cancer risk.
• Leukoplakia and erythroplakia: stopping tobacco and alcohol, biopsy, and removal of patches with dysplasia, followed by monitoring.
• Oral cancer: surgery, often with radiation or chemotherapy, planned by a head and neck cancer team.

Preventing tongue lesions

• Stop smoking and chewing tobacco, and limit alcohol. Together they multiply the risk of oral cancer.
• Get dental checkups at least once a year. Dentists screen for oral cancer at each visit.
• Fix broken teeth and poorly fitting dentures promptly.
• Rinse your mouth after using a steroid inhaler.
• Consider HPV vaccination, which protects against HPV-related throat and tongue-base cancers.

Frequently asked questions

Is a lesion on the tongue a cause for concern?

Usually not. Most tongue lesions are bite injuries, canker sores, inflamed taste buds or thrush, and heal within 2 weeks. See a dentist or doctor if a lesion lasts longer than 2 to 3 weeks, feels hard, bleeds easily, is a red or fixed white patch, or if you smoke or drink heavily.

What causes white lesions on the tongue?

White lesions that wipe off are usually thrush. Those that move around are geographic tongue. Fixed white patches can be friction keratosis, lichen planus, hairy leukoplakia or leukoplakia, which needs a biopsy. A painful white spot with a red rim is usually a canker sore.

Why do I keep getting lesions on the side of my tongue?

Repeated sores on the side of the tongue are most often caused by biting, a sharp tooth, a broken filling or a denture edge. Recurrent canker sores are another cause. If the sore stays in one place and does not heal within 3 weeks, have it examined.

What do cancerous tongue lesions look like?

Early tongue cancer usually appears as a persistent ulcer with firm, raised edges, or a red or red-and-white patch on the side or underside of the tongue. It often does not hurt at first. It may bleed easily and slowly enlarge. Only a biopsy can confirm it.

How long do tongue lesions take to heal?

Bite injuries and canker sores usually heal in 7 to 14 days. Lie bumps fade in 1 to 3 days. Herpes sores heal in about 10 days. Thrush clears within 1 to 2 weeks of treatment. Anything still present after 3 weeks needs a professional look.

What are benign tongue lesions?

Benign tongue lesions include traumatic ulcers, canker sores, lie bumps, geographic tongue, fibromas from repeated biting, papillomas and mucoceles. They do not spread or turn into cancer, though a doctor may remove a lump to confirm what it is.