Mouth ulcers

Mouth ulcers can be a pain – often appearing after you’ve bitten your cheek or lip or from wearing poorly fitted dentures or braces. Using Kenalog in Orabase® can help relieve the pain and discomfort, while speeding up healing process.

mouth ulcers

What are mouth ulcers?

Mouth ulcers commonly appear as round or oval sores that develop just after you’ve damaged or irritated the soft moist skin lining the inside of your mouth (called the mucosal membrane). They can be white, red, yellow or grey in colour and look like small craters with swollen, raised edges.

There are lots of nerves close to the skin’s surface in your mouth, which means that mouth ulcers can be very painful. Everyday things such as eating and drinking can irritate the sores and it can be painful just to chew food or brush your teeth.

When untreated, mouth ulcers will usually heal themselves within 7 to 10 days.

mouth ulcers
mouth ulcers
mouth ulcers
mouth ulcers

What causes mouth ulcers?

Mouth ulcers are a common problem, but we don’t always know the reasons why they develop.

Most mouth ulcers are often the result of accidental damage to the lining of your mouth through things such as:

  • Biting your lip, tongue or cheek
  • Slipping with your toothbrush and bumping the inside of your mouth or gums
  • Damage form a sharp tooth or filling
  • Rubbing of ill-fitting dentures or braces
  • Eating hard or sharp-edged foods
  • Burning your mouth with hot food or drinks

Other causes can include:

  • Infections such as cold sores, chicken pox, shingles and oral thrush
  • Food allergies
  • Certain medications or medical treatments – such as non-steroidal anti-inflammatory drugs (NSAIDs), beta blockers, chemotherapy or radiotherapy.

Some people are more prone to getting reoccurring ulcers (called aphthous ulcers). The reason why these ulcers keep returning is not always clear but it is thought that certain things can act as triggers, such as:

  • Stress or anxiety
  • Hormonal changes – particular during a woman’s monthly period or during pregnancy
  • A poor diet – which may lead to nutritional deficiencies such as vitamin B12, iron or folic acid
  • Beginning to quit smoking cigarettes
  • Having a gastrointestinal disease such as Crohn’s or coeliac disease
  • Your genes – having ulcers can sometimes run in families!

How to treat mouth ulcers

Most mouth ulcers will usually heal up and go way in a couple of weeks. In the meantime, here are a few things you can try to help manage any painful symptoms:

avoid eating

Avoid eating anything that will irritate your ulcer and make the pain worse, such as hard, spicy or sour foods

drink lots

Drink lots of cool fluids – try using a straw to keep the liquids away from the painful areas

rinse mouth

Give you mouth a regular rinse out with warm, slightly salty water


Try to keep your mouth clean – use a soft toothbrush and brush gently

If your ulcer becomes very painful then you may want to use some form of medication. The main aim of any treatment is to lessen the pain or discomfort caused by the ulcer and help promote healing. The type of medication you use will depend on how much pain and discomfort you are in and what may have caused your ulcer and can include:

  • Pain-relieving mouthwashes, sprays or gels (available from your pharmacy) to help reduce the pain in the area directly around your ulcer. These usually only work for a short time.
  • Medicated antiseptic mouthwashes such as those containing chlorhexidine gluconate (available from your pharmacy) reduce the build up of bacteria in your mouth and help prevent your ulcer becoming infected.
  • Steroid-containing* protective pastes, such as Kenalog in Orabase®, provide rapid pain relief by reducing the inflammation associated with ulcers. The paste also forms a protective film over the ulcer, protecting it from further irritation and damage, providing an environment for accelerated healing. Kenalog in Orabase® is available from your local pharmacy without a prescription after consultation with your pharmacist.

*Steroid-containing medications are not suitable if you have a viral, bacterial or fungal infection in your mouth or throat as they can make these infections worse.

Preventing mouth ulcers

Preventing mouth ulcers can be a bit tricky when the cause is not known or is out of your control, but there are a few things you can do to reduce the likelihood of them developing:

  • Remember to take care and brush your teeth gently with a soft toothbrush
  • Eat a healthy well-balanced diet
  • Keep any underlying medical conditions well-controlled
  • See your dentist about any broken teeth, rough surfaces, or ill-fitting dentures
  • Make sure your dentures or braces are not broken and fit properly

Learn More

woman smiling
It is important to see your doctor if your mouth ulcer is taking more than 3 weeks to heal, has an unusual appearance, is very painful, other sores appear on your body, or if you get ulcers frequently.