What mouth ulcers are
Mouth ulcers are small, painful sores inside the mouth, on the inner cheeks, lips, tongue or gums. The most common type, called aphthous ulcers, are round or oval with a white or yellow centre and a red border. They can make eating, drinking and brushing painful for a few days.
Mouth ulcers are very common and are not contagious. Most heal on their own within one to two weeks without leaving a scar. Some people get them again and again, often at times of stress, illness or poor sleep. Larger ulcers can take several weeks to heal and may leave a small scar.
Common causes of mouth ulcers
Often no single cause is found for an ulcer, and different people have different triggers. Several factors are known to trigger mouth ulcers or make them more likely, and knowing yours helps prevent repeat episodes. The common ones include the following.
- Biting the cheek, a sharp tooth, braces or ill-fitting dentures
- Hard toothbrush or brushing too hard
- Stress, poor sleep and hormonal changes around periods
- Low iron, vitamin B12 or folate
- Very spicy, sour or hot foods in sensitive people
- Viral infections such as herpes (cold sores) or hand, foot and mouth disease in children
- Some medicines and conditions such as coeliac disease or inflammatory bowel disease
When an ulcer could be serious
Oral cancer is common in India, largely because of tobacco chewing, gutka, paan with tobacco, smoking and alcohol. An early oral cancer can look like an ulcer that does not heal, or a red or white patch that does not go away. It is often painless in the early stages, so people may ignore it.
Any ulcer or patch that has not healed after three weeks, especially in a tobacco or alcohol user, must be checked by a doctor or dentist without delay. Do not keep changing gels and home treatments for weeks. Early diagnosis of oral cancer makes treatment much simpler and far more successful.
How mouth ulcers is diagnosed
Most mouth ulcers are diagnosed by simply looking at them and asking about your symptoms. If ulcers keep coming back or are unusually large, the doctor may order blood tests for anaemia, iron, vitamin B12 and folate, and sometimes tests for coeliac disease.
If an ulcer looks unusual, feels hard, bleeds easily or does not heal, the doctor or dentist may take a small tissue sample, called a biopsy, to check for cancer or other conditions. Ulcers that come with sores on the genitals, eye redness or joint pain may point to a wider condition and need further tests.
Treatment and relief
Treatment aims to ease pain and help healing. A pharmacist can suggest a numbing gel, a protective paste or an antiseptic mouthwash, used as the label advises. Chlorhexidine mouthwash may cause temporary brown staining of teeth. For painful or frequent ulcers, a doctor may prescribe a steroid paste or mouthwash for a short time.
If blood tests show low iron, B12 or folate, the doctor will prescribe supplements. Herpes infections may need antiviral medicine, only on a doctor's prescription. Numbing gels containing benzocaine or similar should not be used in young children without advice.
Self-care at home
These simple steps can reduce pain, protect the ulcer from further injury and help it heal faster. Children, pregnant women and people with diabetes or low immunity should see a doctor if ulcers are frequent, very painful or slow to heal, as they may need specific treatment.
- Use a soft toothbrush and a mild toothpaste
- Rinse with lukewarm salt water after meals
- Eat soft, cool foods such as curd rice, idli and bananas
- Avoid very spicy, sour, salty or hot foods until healed
- Drink plenty of water and use a straw if drinking hurts
- Stop tobacco and alcohol completely
When to see a doctor for mouth ulcers
See a doctor or dentist if an ulcer lasts more than three weeks, keeps coming back, is very large or painful, or comes with fever or ulcers elsewhere on the body. A doctor or pharmacist can suggest the right gel or mouthwash, and a dentist can fix sharp teeth or dentures that cause repeated injury.
Medicines doctors commonly use
Only your doctor can decide which medicine, dose and combination is right for you.
- Local anaesthetic gels such as lidocaine or benzocaineNumb the ulcer to ease pain while eating.Follow the label or your pharmacist's advice; not for young children without advice.
- Protective pastes or gelsForm a coating over the ulcer to reduce pain and irritation.Follow the label or your pharmacist's advice.
- Chlorhexidine mouthwashReduces germs and helps prevent infection of ulcers.Follow the label; can temporarily stain teeth brown.
- Topical steroid pastes or mouthwashes such as triamcinoloneReduce swelling and pain and speed healing of severe ulcers.Only on a doctor's or dentist's prescription, for short-term use.
- Vitamin B12, folate or iron supplementsCorrect deficiencies that can cause repeated ulcers.Take only if a blood test shows a deficiency and as your doctor advises.
See a doctor urgently if
- See a doctor or dentist soon if a mouth ulcer or patch has not healed after three weeks.
- See a doctor soon if you have a red or white patch, lump or thickening in the mouth, especially if you use tobacco.
- See a doctor soon if ulcers come with fever, weight loss or ulcers on the genitals or eyes.
- See a doctor urgently if a child with mouth ulcers refuses to drink and shows signs of dehydration.
- See a doctor soon if ulcers are very frequent or getting bigger.
Tests that may help
This article is general health information, not medical advice. Do not start, stop or combine medicines on your own — always follow your doctor's prescription and ask your pharmacist if unsure.