Mouth ulcers are common and should clear up on their own within a week or 2. But see a GP or dentist if you have a mouth ulcer that lasts longer than 3 weeks.
1. Causes of 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
Sometimes they're triggered by things you cannot always control, such as:
- hormonal changes – such as during pregnancy
- your genes – some families get mouth ulcers more often
- a vitamin B12 or iron deficiency
- medicines – including some NSAIDs, beta blockers or nicorandil
- stopping smoking – people may develop mouth ulcers when they first stop smoking
If you have several mouth ulcers, it 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
- Crohn's disease and coeliac disease (conditions that affect the digestive system)
- a weakened immune system from having a condition like HIV or lupus
2. How you can treat mouth ulcers yourself
Mouth ulcers are rarely a sign of anything serious but may be uncomfortable to live with.
They need time to heal and there's 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:
- do not eat very spicy, salty, or acidic food
- do not eat rough, crunchy food, such as toast or crisps
- do not drink very hot or acidic drinks, such as fruit juice
- do not use chewing gum
- do not use a toothpaste containing sodium lauryl sulfate
3. Treatment from a dentist or GP
A GP or dentist may prescribe stronger medicine to treat severe, persistent, or infected mouth ulcers.
Possible treatments include:
- steroid mouth spray or steroid tablets that dissolve in your mouth
- painkilling gels, ointments, sprays, or tablets
- mouthwashes to kill or remove any germs in your mouth.