Oral thrush


Oral thrush is caused by an infection with yeast from the Candida family. Overgrowth of this yeast can occur in several parts of the body, but is most common in the mouth or the vagina.

Both children and adults can get oral thrush, but it's much more common in young babies.

Oral thrush is usually harmless, but the symptoms can be bothersome, so it may need some treatment.

Oral thrush in babies

About one in seven babies develop oral thrush during childhood. It's most common when they are under 12 weeks old.

Your baby is more at risk of oral thrush if they have had a recent course of antibiotics, or if you are breastfeeding and have taken antibiotics yourself. It can also occur spontaneously because babies' immune systems are less developed than adults.

Babies who have thrush will develop white spots in their mouth, and may form white, grey or yellow patches on their tongue. These patches are difficult to remove and you won't be able to wipe them off the surface of the tongue. Your baby may not be bothered by these spots at all, but some babies stop feeding when they have thrush.

Thrush can be passed on through contact, so if you're breastfeeding a baby with thrush, you may develop thrush of the nipple. This will make your nipples sore and itchy but can be treated with simple creams available at your pharmacy.

If your baby's tongue has a white coating that wipes off easily, or disappears between feeds, this is probably just milk coating it. This is completely harmless, and you don't need to worry about speaking to your doctor or pharmacist unless you're concerned.

Preventing & treating oral thrush in babies

If your baby is having difficulty feeding, or appears uncomfortable with signs of thrush, they may need some simple treatment. If your child is over four months old, speak to your pharmacist who may recommend an oral gel if they judge that treatment is necessary.

If your child is younger than four months old, or if there is no improvement after one week of treatment with the oral gel, you should see your Doctor.

Preventing thrush can be tricky, as it often occurs unexpectedly, with no obvious cause. Sterilising anything your baby regularly puts in their mouth can help prevent thrush, so sterilising dummies and bottle teats is a good idea.

If your baby gets thrush regularly, it's a good idea to see your Doctor to make sure there's no underlying reason for it.

Oral thrush in adults

Adults don't get oral thrush as often as young babies, but there are groups of people who are more at risk such as:

  • People who wear dentures. Areas of thrush can sometimes occur underneath the denture sites
  • People taking antibiotics
  • People who have dry mouths. This can be a side effect of medicines, or because of certain medical conditions
  • People who have certain medical conditions, such as diabetes, HIV, or those on certain treatments, such as steroid treatment, or chemotherapy, as well as some treatments for inflammatory bowel disease and arthritis
  • People who are anemic
  • People who smoke
  • People who use steroid inhalers for asthma or COPD
  • People who are frail or elderly

The symptoms of thrush in adults can be similar to those in children, but you may only have red, sore patches of the inside surface (mucosa) of your mouth. Eating and drinking can become painful or uncomfortable with oral thrush. You may also find your sense of taste changes slightly.

Preventing & treating oral thrush in adults

Treatment for mild thrush is available from pharmacies. It is in the form of an oral gel and treatment usually lasts for at least seven days – your pharmacist can advise you about the specifics.  Make sure you see your Doctor if you don't see any improvement after using the oral gel for one week, if your oral thrush is severe or if you have pain when swallowing. 

You can help to prevent thrush by understanding your risk factors:

  • If you are diabetic, keeping your blood sugar well controlled may help in preventing oral thrush
  • If you use steroid inhalers, using a spacer device and rinsing your mouth can help prevent thrush
  • If you wear dentures, make sure you follow the cleaning recommendations that your dentist has given you
  • Consider going for a check-up with your dentist to make sure your dentures fit properly, and make sure you don't wear them at night
  • If you have a dry mouth, aim to keep it moist by sipping water frequently
  • If you have anemia, or vitamin deficiencies, your Doctor will be able to test for these and advise you how best to replace these vitamins. Changing or supplementing your diet could help prevent thrush in the future
    If you're at a high risk of oral thrush or have had it frequently, visit your Doctor.

Next Steps

 If you think you or your baby may have oral thrush, see your pharmacist for advice

  • If your child is under four months old and you think they may have thrush, see your Doctor for advice
  • If you're worried about your or your baby's symptoms, see your Doctor for some advice
  • If you develop oral thrush as an adult, see if you can change anything in your lifestyle that may help you avoid getting thrush again
  • Keep up a good oral hygiene routine and ask your dentist for advice if you're unsure of anything