Mouth ulcers

Mouth ulcers are an extremely common type of sore found in the mouth, usually on the inside of your lips, your tongue, inside the cheek, or on the sides of your gums.

They can be of various sizes and are often uncomfortable. Most ulcers are harmless and resolve themselves without any treatment. Around 20% of people experience recurrent mouth ulcers, also known as aphthous ulcers. Recurrent ulcers or ulcers that don’t heal may require treatment and could be a sign of an underlying health condition.

Mouth ulcers are not contagious and are sometimes referred to as canker sores.

Types of mouth ulcers:

Minor - Minor ulcers are between 2mm and 8mm across and usually take up to two weeks to heal. They usually only cause minor pain.

Major - These mouth ulcers are larger than 8mm in diameter and the lesions can be raised, deep and irregular in shape. They may also take up to six weeks to heal and may leave some scarring.

Herpetiform ulcers (HU)- These are a subtype of aphthous ulcers which appear as very small or pinpoint mouth ulcers in clusters of 10 – 100. They get their name as they resemble the sores associated with herpes. However, they are not infectious.

They most commonly occur in adults and resolve themselves within a few weeks. They don’t usually leave a scar.

What are the symptoms of mouth ulcers?

Ulcers can be painful when eating, drinking and brushing your teeth. Poor oral hygiene can often make the pain worse. The exact symptoms of the mouth ulcer will depend on what type of ulcer a person has.

Symptoms of minor and major ulcers may include:

  • one or more sores on the inside of your cheeks, the roof of your mouth, gums or tongue

  • round lesions with red edges that are yellow, grey or white in the middle

  • fever, sluggishness or swollen glands, if the outbreak is extreme

Signs of HU may include:

  • mouth lesions that are extremely painful and can appear anywhere in the mouth

  • ulcers that recur quickly which gives the impression that the infection is continuous

  • ulcers that increase in size to eventually form one large ulcer

  • lesions that take more than 10 days to heal

What causes mouth ulcers?

While there is no one specific cause for mouth ulcers, there are certain factors that can lead to their development, which include:

  • biting the inside of your cheek

  • injury or trauma to the mouth, including slipping with your toothbrush when brushing your teeth

  • rubbing against braces or dental apparatus

  • rubbing against broken or misaligned teeth

  • burns from hot food

  • spicy or acidic foods

  • sensitivity to toothpaste or mouth wash

  • reactions to medications such as pain relief or beta-blockers

  • deficiency in vitamins B-12, folate, iron, and zinc

  • hormonal changes such as those during puberty, pregnancy and menopause

  • stress, anxiety or extreme fatigue

  • skin rashes in the mouth, such as lichen planus

  • other bacterial, fungus or viral infections, including the herpes simplex viral infection (cold sores)

Mouth ulcers can also be the sign of underlying health conditions, including:

  • coeliac disease

  • Crohn’s disease

  • inflammatory bowel disease

  • HIV/AIDS

  • diabetes

  • Behcet’s disease

  • oral cancer

What are the complications of mouth ulcers?

Most mouth ulcers heal on their own and only cause temporary pain or difficulty while eating and drinking. However, some ulcers may heal with scarring, while others can lead to bacterial infections, or even increase the risk of developing oral cancer.10

How to treat and heal mouth ulcers

Most mouth ulcers will usually heal on their own within 10 to 14 days, and won’t require any treatment, although over-the-counter (OTC) pain relief medication or an anaesthetic mouth gel may be needed to relieve pain. Your MediADVICE pharmacist will be able to advise you on what products may be suitable.

However, recurrent ulcers or those caused by the herpes simplex infection may require a topical treatment such as a mouthwash, ointment or gel. In severe cases, it may be necessary for immunosuppressant medication.

To help heal ulcers, we suggest the following:

  • avoid touching the ulcer where possible and if you have to, make sure you wash your hands before and after

  • use a soft toothbrush when cleaning your teeth, or mouthwash if ulcers are too painful for a toothbrush

  • rinse your mouth with salt water (one teaspoon to one cup of water) several times a day, holding the water in your mouth for two minutes and then spitting out

  • eat soft food

  • avoid acidic or spicy foods

  • drink through a straw

  • drink cool water to ease pain

  • take over-the-counter (OTC) pain relief medication, when needed

To help heal ulcers, we suggest the following:

  • avoid touching the ulcer where possible and if you have to, make sure you wash your hands before and after

  • use a soft toothbrush when cleaning your teeth, or mouthwash if ulcers are too painful for a toothbrush

  • rinse your mouth with salt water (one teaspoon to one cup of water) several times a day, holding the water in your mouth for two minutes and then spitting out

  • eat soft food

  • avoid acidic or spicy foods

  • drink through a straw

  • drink cool water to ease pain

  • take over-the-counter (OTC) pain relief medication, when needed

When should you see your doctor for mouth ulcers?

If your mouth ulcers do not heal within two weeks, or they interfere with your daily living you should see your doctor. You should also seek medical advice if you experience any of the following:

  • mouth ulcers that extend to your lips

  • unusually large ulcers

  • painless ulcers

  • painful ulcers that can’t be managed with OTC pain medication

  • new ulcers appear before the old ones have healed

  • problems eating or drinking

  • weight loss

  • high fever and diarrhea

Your local MediADVICE pharmacist is available to help you manage your health. Speak to your MediADVICE pharmacist about your mouth ulcers so we can recommend products and medications that may be suitable for you.

Find your local pharmacy

Disclaimer

General advice only – this information should not replace the information provided to you by your health care professional. If symptoms are severe or persist, please speak to your health care professional. Information current as of date of publishing.

References:

1Healthdirect, Mouth sores and ulcers,https://www.healthdirect.gov.au/mouth-sores-and-ulcers
2Better Health Channel, Mouth ulcers,https://www.betterhealth.vic.gov.au/health/conditionsandtreatments/mouth-ulcers
3Medical News Today, Everything you need to know about mouth ulcers,https://www.medicalnewstoday.com/articles/317984
4Healthline, What Causes Mouth Ulcers and How to Treat Them,https://www.healthline.com/health/mouth-ulcers
5Medical News Today, Everything you need to know about mouth ulcers,https://www.medicalnewstoday.com/articles/317984
6Better Health Channel, Mouth ulcers,https://www.betterhealth.vic.gov.au/health/conditionsandtreatments/mouth-ulcers
7Medical News Today, Everything you need to know about mouth ulcers,https://www.medicalnewstoday.com/articles/317984
8Healthline, What Causes Mouth Ulcers and How to Treat Them,https://www.healthline.com/health/mouth-ulcers
9Healthline, What Causes Mouth Ulcers and How to Treat Them,https://www.healthline.com/health/mouth-ulcers
10DermNet NZ, Mouth ulcer,https://dermnetnz.org/topics/mouth-ulcer
11Better Health Channel, Mouth ulcers,https://www.betterhealth.vic.gov.au/health/conditionsandtreatments/mouth-ulcers
12Better Health Channel, Mouth ulcers,https://www.betterhealth.vic.gov.au/health/conditionsandtreatments/mouth-ulcers
13Healthdirect, Mouth sores and ulcers,https://www.healthdirect.gov.au/mouth-sores-and-ulcers
14Healthline, What Causes Mouth Ulcers and How to Treat Them,https://www.healthline.com/health/mouth-ulcers