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Mouth ulcers

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Mouth ulcers are common and should clear up on their own within a week or two. They're rarely a sign of anything serious but may be uncomfortable to live with.

How you can treat mouth ulcers yourself

Mouth ulcers need time to heal and there is no quick fix. Avoiding things that irritate your mouth ulcer should help:

  • speed up the healing process
  • reduce pain
  • reduce the chance of it returning

Do

  • use a soft-bristled toothbrush
  • drink cool drinks through a straw
  • eat softer foods
  • get regular dental check-ups
  • eat a healthy, balanced diet

Don't

  • eat very spicy, salty or acidic food
  • eat rough, crunchy food, such as toast or crisps
  • drink very hot or acidic drinks, such as fruit juice
  • use chewing gum
  • use toothpaste containing sodium lauryl sulphate

A pharmacist can help with mouth ulcers

A pharmacist can recommend a treatment to speed up healing, prevent infection or reduce pain, for example:

  • antimicrobial mouthwash
  • a painkilling mouthwash, gel or spray
  • corticosteroid lozenges

You can buy these without a prescription but they may not always work.

Find a pharmacy

See a dentist or GP if your mouth ulcer:

  • lasts longer than 3 weeks
  • keeps coming back
  • becomes more painful and red – this may be a sign of an infection

Although most mouth ulcers are harmless, a long-lasting mouth ulcer is sometimes a sign of mouth cancer. It's best to get it checked.

Treatment from a dentist or GP

Your GP or dentist may prescribe stronger medication to treat severe, recurrent or infected mouth ulcers.

Check if you have a mouth ulcer

You may have more than one ulcer at a time and they can change in size.

Mouth ulcers aren't contagious and shouldn't be confused with cold sores. Cold sores appear on the lips or around the mouth and often begin with a tingling, itching or burning sensation.

If you have several mouth ulcers, this can be a symptom of:

  • hand, foot and mouth disease, which also causes a rash on the hands and feet
  • oral lichen planus, which causes a white, lacy pattern inside the cheeks

You can't always prevent mouth ulcers

Most single mouth ulcers are caused by things you can try to avoid, such as:

  • biting the inside of your cheek
  • badly fitting dentures, braces, rough fillings or a sharp tooth
  • cuts or burns while eating or drinking – for example, hard food or hot drinks
  • a food intolerance or allergy
  • damaging your gums with a toothbrush or irritating toothpaste
  • feeling tired, stressed or anxious

Sometime they're triggered by things you can't always control, for example:

  • hormonal changes – such as during pregnancy
  • your genes – some families get mouth ulcers more often
  • a long-term condition – such as inflammatory bowel disease (IBD), coeliac disease or Behçet's disease
  • a vitamin B12 or iron deficiency
  • medications – including some NSAIDs, beta-blockers or nicorandil
  • stopping smoking – people may develop mouth ulcers when they first stop smoking

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