Mouth ulcer home remedies can bring real comfort when a small, painful sore makes eating, drinking and even talking difficult. The good news is that most mouth ulcers are harmless and heal by themselves within one to two weeks. Simple care at home can ease the pain and protect the sore while it heals. This guide shares 9 safe ways to soothe a mouth ulcer, explains what causes it, and tells you when an ulcer needs to be checked by a doctor or dentist.
Please note: This article is general information, not personal medical advice. A mouth ulcer that does not heal within three weeks must always be checked by a doctor or dentist. Read our Medical Disclaimer.
What Is a Mouth Ulcer?
A mouth ulcer, also called a canker sore or aphthous ulcer, is a small, round or oval sore with a white or yellow centre and a red edge. It appears inside the cheeks, on the lips, tongue or gums. Mouth ulcers are not contagious, and they are different from cold sores, which usually appear outside the mouth on the lips and are caused by a virus.
Common Causes of Mouth Ulcers
Minor Injury
Biting your cheek, a sharp or broken tooth, braces or harsh brushing.
Stress and Poor Sleep
Stress is a common trigger for repeated ulcers. See our guide on how to reduce stress.
Nutrient Deficiency
Low iron, vitamin B12 or folate can make ulcers more frequent.
Food Triggers
Very spicy, acidic or salty foods, and some toothpastes, can irritate the mouth.
Other causes include hormone changes, some medicines, quitting smoking, and conditions such as coeliac disease or inflammatory bowel disease. In many people, no clear cause is found.
9 Mouth Ulcer Home Remedies
1. Rinse with Warm Salt Water
Stir half a teaspoon of salt into a glass of warm water. Swish it gently around your mouth for 30 seconds and spit it out. It can clean the area and ease discomfort. It may sting for a moment, but it often helps. Repeat 2 to 3 times a day.
2. Try a Baking Soda Rinse
Dissolve half a teaspoon of baking soda in a glass of warm water and use it as a mouth rinse. It can help reduce the acidity in the mouth and soothe irritation. Do not swallow it.
3. Eat Cool, Plain Yoghurt
Plain yoghurt is soft, cool and gentle on a sore mouth, which makes it easy to eat when everything else hurts. Some people believe the friendly bacteria in yoghurt help ulcers heal, but the scientific proof for this is limited. Choose plain yoghurt without added sugar, and use it as a soothing food rather than a cure.
4. Suck on Ice Chips or Have Cold Drinks
Cold numbs the area for a short time and can reduce pain. Let a small piece of ice melt slowly near the ulcer, or sip cold water. Avoid very hot drinks.
5. Dab a Little Honey
Small studies suggest that honey may help soothe mouth ulcers and support healing. Dab a small amount on the sore with a clean finger or cotton bud a few times a day. Do not use honey on babies under 12 months old, because of the risk of infant botulism.
6. Choose Soft, Bland Foods
Eat soft foods such as khichdi, porridge, mashed banana, boiled eggs, soup and mashed potato. Avoid spicy, salty, acidic and sharp foods, such as chillies, pickles, citrus fruits, tomato sauce, chips and crusty bread, until the ulcer heals.
7. Brush Gently with a Soft Toothbrush
Keep your mouth clean to avoid infection, but use a soft toothbrush and brush gently around the ulcer. If your toothpaste seems to trigger ulcers, ask your dentist about a toothpaste without sodium lauryl sulphate (SLS).
8. Use an Over-the-Counter Gel or Mouthwash
Pharmacies sell gels, pastes and mouthwashes for mouth ulcers. Some form a protective layer over the sore, some numb the area, and some contain antiseptic. Ask a pharmacist which is suitable for you and follow the instructions on the label. These products are not suitable for young children unless a doctor or pharmacist advises it.
9. Look After Your Diet and Stress
If you get mouth ulcers often, make sure you eat enough iron-rich, B12-rich and folate-rich foods, such as daal, green leafy vegetables, eggs, dairy, fish and meat, and manage stress and sleep. See our guide to affordable high-protein foods for budget-friendly ideas. Do not take supplements without a blood test and a doctor’s advice.
Quick Guide to Mouth Ulcer Home Remedies
| Remedy | What It Does | Caution |
|---|---|---|
| Warm salt water rinse | Cleans and eases discomfort | Do not swallow; may sting |
| Baking soda rinse | Soothes irritation | Do not swallow |
| Plain yoghurt | Soft, cooling food | Evidence for healing is limited |
| Ice chips or cold drinks | Temporary numbing | Avoid very cold on sensitive teeth |
| Honey | May soothe and support healing | Never for babies under 12 months |
| Soft, bland foods | Avoids more irritation | Avoid spicy and acidic foods |
| Pharmacy gels and mouthwashes | Protect or numb the sore | Ask a pharmacist; check age limits |
Mouth Ulcer or Cold Sore?
| Feature | Mouth Ulcer (Canker Sore) | Cold Sore |
|---|---|---|
| Where | Inside the mouth | Usually on or around the lips |
| Cause | Often unclear; injury, stress, deficiencies | Herpes simplex virus |
| Looks like | A white or yellow sore with a red edge | A cluster of small blisters that crust over |
| Contagious | No | Yes |
What to Avoid
- Picking, scratching or bursting the ulcer. It can delay healing and lead to infection.
- Hot, spicy, salty and acidic foods and drinks while the ulcer is sore.
- Mouthwashes with a lot of alcohol, which sting and dry the mouth.
- Tobacco, betel quid (paan), gutka, supari and naswar. They irritate the mouth and can cause serious mouth disease.
- Putting tablets such as aspirin directly on the ulcer. It can burn the lining of the mouth.
- Undiluted peroxide or strong chemicals in the mouth.
- Ignoring an ulcer that does not heal.
When to See a Doctor or Dentist
See a doctor or dentist without delay if a mouth ulcer lasts longer than 3 weeks, even if it is painless. Persistent ulcers, red or white patches in the mouth, a lump, or unexplained bleeding can be early signs of mouth cancer, especially in people who use tobacco, paan, gutka or naswar, or who drink alcohol.
Please also seek medical advice if:
- Ulcers are very large, very painful, or keep coming back
- You have many ulcers at once, or they spread to the lips and face
- You have a fever, a rash, swollen glands, or trouble swallowing, eating or drinking
- You have ulcers along with diarrhoea, weight loss, tiredness, red eyes or sores elsewhere on the body
- A child has mouth ulcers with a fever or refuses to drink, because the child may have an infection that needs a doctor
- You take regular medicines and the ulcers began after starting a new one
A doctor may check for iron, vitamin B12 and folate deficiency or other conditions, and a dentist can fix a sharp tooth or ill-fitting braces or dentures.
How to Prevent Mouth Ulcers
- Eat a balanced diet with enough iron, B12 and folate.
- Brush gently with a soft brush, and see a dentist about sharp edges on teeth, braces or dentures.
- Notice your triggers such as spicy foods, certain toothpastes or stress, and avoid them where you can.
- Drink enough water and avoid dry, rough food when your mouth is sore.
- Do not use tobacco, paan, gutka or naswar.
Frequently Asked Questions
How long do mouth ulcers last?
Most minor mouth ulcers heal by themselves within one to two weeks. Larger ulcers can take longer. See a doctor or dentist if an ulcer lasts more than three weeks.
What is the fastest of the mouth ulcer home remedies?
Warm salt water rinses, cold foods, soft bland meals and a protective pharmacy gel usually give the quickest relief from pain. Healing itself still takes several days.
Does yoghurt help mouth ulcers?
Plain yoghurt is cool and soft, so it is comfortable to eat when your mouth is sore. Proof that it speeds healing is limited, but it is a safe food to enjoy.
Are mouth ulcers contagious?
No, ordinary mouth ulcers cannot be passed on by kissing or sharing food. Cold sores, which are caused by a virus, are contagious.
Are mouth ulcer home remedies safe for children?
Soft, cool foods and gentle cleaning are fine. Honey must never be given under 12 months, and many gels and mouthwashes are not suitable for young children, so ask a doctor or pharmacist.
Conclusion
Mouth ulcers are common, annoying and usually harmless. Mouth ulcer home remedies such as warm salt water rinses, cool soft foods like plain yoghurt, honey for those over one year old, gentle brushing and avoiding spicy or acidic food can ease the pain while the ulcer heals. Do not ignore an ulcer that lasts more than three weeks, and see a doctor or dentist if ulcers are large, frequent or come with other symptoms. For more oral care advice, read our guide to toothache home remedies, and explore our Home Remedies section.
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Last updated: October 2026. This article has not been medically reviewed.