Mouth ulcers – symptoms and solutions

Mouth ulcers appear on the inside of your mouth and can be very painful but they’re usually harmless. Find the best treatment plus how to prevent them.

What do they look and feel like?

What causes mouth ulcers?

Self-care for mouth ulcers

When to see a dentist or doctor and getting diagnosed

Treatment from your doctor or dentist

How to prevent mouth ulcers

Mouth ulcers, also called canker sores, are common. They can be caused by ‘sharp’ tasting food, stress, or a vitamin deficiency. Most heal by themselves, but there are several ways to treat mouth ulcers – and stop them coming back.

If you’ve never had a mouth ulcer, you’re lucky! Experts think around 10% of people worldwide will get them at some point, but it’s hard to say exactly how many of us are affected. 

Having a mouth ulcer can make it painful to talk, eat, or drink, stop you eating your favorite foods, or from kissing your partner. But they’re not contagious; mouth ulcers are not the same as [cold sores](https://www.livehealthily.com/health-library/conditions/cold-sore). 

Cold sores appear on the outside of your lips and around your mouth, and are caused by the herpes simplex virus. You’ll normally get a tingling or burning sensation before they appear.   

Mouth ulcers are not caused by a virus, and you don’t usually need to treat them as they will clear up on their own in 1-2 weeks. But you can get treatment to help reduce pain or swelling.


## What do they look and feel like?
Mouth ulcers are tiny sores are normally round, with a white or yellow center and a red rim. They tend to form inside your mouth – on your cheeks, lips, or on your tongue – and you may get more than 1 ulcer at the same time.

Apart from the mouth ulcer itself, you might also notice pain and swelling around the sore. The pain may get worse when you eat sour, spicy, or salty foods, or brush your teeth.


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## What causes mouth ulcers?
A single mouth ulcer is normally caused by damage to the inside of your mouth. This could be from:
- accidentally biting your cheek or tongue
- sharp teeth or a piece of hard food
- wearing dentures, braces or a retainer
- a rough or broken filling 
- brushing your teeth too vigorously or using a toothpaste that irritates your mouth.

These ‘traumatic ulcers’ normally clear up once the damage that caused them has gone.

If your mouth ulcers keep coming back, this could be due to:
- viral infections including the cold sore virus and chickenpox
- stress or anxiety
- hormonal changes, such as around your period – canker sores are more common in females 
- a vitamin deficiency, such as iron, B12 or zinc
- certain medications, including ibuprofen or treatments for angina
- irritation from smoking or chewing tobacco
- some medical conditions – such as [Crohn's disease](https://www.livehealthily.com/health-library/conditions/crohns-disease) (inflammation of the digestive system lining) and [coeliac disease](https://www.livehealthily.com/health-library/conditions/coeliac-disease) (where the body reacts to gluten).

If you have clusters of mouth ulcers, this could be [hand, foot and mouth disease](https://www.livehealthily.com/health-library/conditions/hand-foot-and-mouth-disease) – you will also get a rash on your hands and feet. However, this virus normally affects young children, so see your doctor if you’re not sure.


## Self-care for mouth ulcers
Most mouth ulcers clear up on their own but there are some things you can do to help them heal and relieve any pain or inflammation. 

Try to avoid anything that could irritate the ulcer, so:
- use a soft toothbrush to clean your teeth
- don’t use toothpastes with sodium lauryl sulphate 
- drink cold drinks through a straw
- avoid spicy, salty or acidic foods
- eat soft foods and avoid ‘sharp’ foods such as crisps or toast.

You could also make a saltwater mouthwash and rinse your mouth out a few times a day.

### Over-the-counter treatments
A pharmacist can also recommend various treatments to help ease the symptoms of mouth ulcers and speed up healing. 

These include:
- antiseptic or antimicrobial mouthwashes
- pain-relieving and/or anesthetic gels, sprays or pastes
- steroid tablets or lozenges.

Taking painkillers like acetaminophen (paracetamol) could also help you feel better. 


## When to see a dentist or doctor and getting diagnosed
If your ulcer is not better in 3 weeks, is getting worse despite treatment, or it’s different to the normal mouth ulcers you get (it could be bigger or near the back of your throat), make an appointment with your doctor or dentist. 

Very rarely, a single mouth ulcer could be a sign of mouth cancer, particularly if it isn’t caused by anything obvious like a sharp tooth, so make an appointment with your doctor as soon as possible, especially if you have other symptoms such as changes in your bowel habits or you don’t feel well.

A doctor can usually diagnose a mouth ulcer by examining it, but you may need blood tests if they suspect you have a health condition.


## Treatment from your doctor or dentist
Treatment depends on the cause. If your mouth ulcers are due to a broken or sharp tooth, see your dentist to get it filed down. They can fix any fillings and adjust badly fitting dentures, too. 

You could also ask them for orthodontic wax to cover the sharp edges on braces or other dental devices.

Treating any underlying health conditions like Crohn’s will also help tackle your mouth ulcer.

For ulcers that are severe, infected, or keep coming back, treatments can include:

- a steroid mouth spray or tablets
- painkillers in gel, ointment, spray, or tablet form
- mouthwashes to get rid of germs in your mouth. 

Your doctor may also prescribe a nutritional supplement if your mouth ulcers are caused by a vitamin deficiency.


## How to prevent mouth ulcers
You can’t prevent every mouth ulcer from developing, but there are some steps you can take to reduce your risk. 

You could:
- lower your stress and anxiety levels with exercise or relaxation methods
- avoid certain foods you know trigger your ulcers
- eat a healthy balanced diet 
- give up smoking and reduce the amount of alcohol you drink
- get regular dental check-ups – this is the best way to keep an eye on any changes in your oral health.


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References

Rosalind Ryan

Jo Wheatley

Dr Emily Blount

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