Mouth Ulcers


Mouth ulcers are little sores that come up inside the mouth, on the tongue or on the gums. Mouth ulcers can be quite painful, but your child doesn’t usually need to see a doctor. 

Causes of mouth ulcers

Several things can cause mouth ulcers:

  • viral infections like cold sores or hand, foot and mouth disease
  • oral thrush
  • injuries like biting, burns or rubbing from braces
  • low vitamin levels
  • diseases like coeliac disease or inflammatory bowel disease

Ulcers that keep coming back without any obvious cause are called aphthous ulcers.

Symptoms of mouth ulcers

Mouth ulcers usually look like round, white sores on the inner lining of your child’s mouth, or on the surface of her gums or tongue.

These sores can be painful, especially when your child eats salty or spicy foods. Sometimes your child might even refuse food until the ulcers begin to heal.

If an infection is causing the ulcers, your child might also have a fever.

When to see a doctor about mouth ulcers

If you think your child might have ulcers related to a mouth infection, it’s a good idea to see your General Practitioner (GP).

You should seek urgent medical advice if your child develops severe mouth ulcers with symptoms of general illness like:

  • weight loss
  • tummy pain
  • unexplained fevers
  • blood or mucus in his poo
  • neck stiffness and tiredness
  • ulcers around his anus

This is because mouth ulcers can sometimes be caused by coeliac disease or inflammatory bowel disease.

Treatment for mouth ulcers

Simple mouth ulcers usually don’t need treatment and will clear up within a week.

If your child is in pain, you can try applying an anaesthetic mouth gel to the area. You can buy these mouth gels over the counter from pharmacies. You can also try warm, salt water rinses if your child is old enough to rinse or gargle with liquids.

Encourage your child to keep up her fluids by giving her small, frequent sips. This will help to prevent dehydration.

There are specific treatments for mouth infections caused by thrush and the cold sore virus – your doctor will let you know about these if your child needs them.