Mouth Ulcers (Chaale): Causes, Relief and Prevention

Reviewed by Dr Asma

Almost everyone gets a mouth ulcer (chaala) at some point. It is a small, round, painful sore inside the cheek, on the tongue or on the gums, and it can make eating, drinking and even talking uncomfortable. The good news is that most mouth ulcers are harmless and heal by themselves within one to two weeks. This guide explains why they appear, what you can do at home, which products can help, and when an ulcer needs a doctor.

What does a mouth ulcer look like?

A typical ulcer is white or yellowish in the centre with a red border. It stings, especially with spicy, salty or sour food. Some people feel a tingling or burning spot a day before it appears. Ulcers are not contagious, which separates them from cold sores (fever blisters) that appear on the outside of the lips and are caused by a virus.

Common causes of mouth ulcers

• Small injuries: biting your cheek, a sharp tooth, rough brushing or ill fitting braces and dentures
• Stress and poor sleep: many people notice ulcers during exams or busy weeks
• Nutritional gaps: low iron, vitamin B12 or folate is a well known trigger for repeated ulcers
• Spicy, acidic or very hot foods that irritate the lining of the mouth
• Hormonal changes, for example around periods
• Certain toothpastes that contain a foaming agent called sodium lauryl sulphate
• Medical conditions such as coeliac disease, inflammatory bowel disease or a weak immune system
• Some medicines, which a doctor or pharmacist can check for you

Simple home care that really helps

• Rinse gently with lukewarm salt water a few times a day. It keeps the area clean and may ease the sting.
• Avoid spicy, salty, sour and very hot foods until the ulcer heals. Cool dahi (yoghurt) and soft foods are easier to eat.
• Use a soft toothbrush and brush carefully around the sore spot.
• Drink plenty of water and avoid smoking, paan, gutka and naswar, which delay healing and are linked with serious mouth disease.
• Do not pick or burst the ulcer, as this invites infection.

Over the counter options

If pain is stopping you from eating, a pharmacist can suggest a numbing gel or an antiseptic mouthwash. A gel such as Bonjela Gel is applied on the sore spot and gives short term relief. Antiseptic rinses may help keep the area clean. You can see the full range of products for this problem in our Mouth Ulcers and Oral Care category. Always read the label and follow the instructions, and ask a pharmacist if you are pregnant, breastfeeding or giving something to a child.

Why do ulcers keep coming back?

If you get ulcers again and again, look for a pattern. Check whether they follow stress, certain foods or a new toothpaste. Repeated ulcers are also a common sign of low iron or vitamin B12. Our guides on iron deficiency anaemia and vitamin B12 deficiency explain the symptoms to watch for. A simple blood test can confirm it, and correcting the deficiency often stops the cycle.

Mouth ulcer or something more serious?

Most ulcers are not dangerous, but see a doctor or dentist without delay if:

• An ulcer has not healed after three weeks
• It is unusually large, very painful, or keeps growing
• You see a red or white patch, a lump or unexplained bleeding in the mouth
• You have a fever, rash, swollen glands or difficulty swallowing
• You have ulcers elsewhere in the body or very frequent outbreaks

A sore that does not heal, especially in people who chew tobacco or paan, should always be examined to rule out oral cancer. Healthy teeth and gums also reduce the chance of ulcers, so if you have gum pain or a broken tooth, read our guide on toothache and bleeding gums.

How to prevent mouth ulcers

• Eat slowly and chew carefully to avoid biting your cheek
• Keep a balanced diet with enough fruit, vegetables, pulses and dairy
• Try a toothpaste without sodium lauryl sulphate if you get frequent ulcers
• Manage stress and keep a regular sleep routine
• Visit your dentist for sharp teeth or poorly fitted dental work

Frequently asked questions

How long does a mouth ulcer last?

A minor ulcer usually heals on its own in one to two weeks. Anything lasting more than three weeks needs a check up.

Are mouth ulcers contagious?

No. Common mouth ulcers cannot be passed on by kissing or sharing food. Cold sores are different and are contagious.

Does constipation or heat in the body cause mouth ulcers?

Many people believe this, but there is no strong proof. Poor diet, stress, dehydration and vitamin gaps are better known triggers.

Can children get mouth ulcers?

Yes. Viral infections are a common cause in children. Offer cool, soft foods and fluids, and see a doctor if your child refuses to drink or has a fever.

Disclaimer: This article is for general information only and is not a substitute for professional medical advice, diagnosis or treatment. Always consult a qualified doctor, dentist or pharmacist before using any medicine.