Frequently asked questions about candida (oral thrush)

What is candida (oral thrush)?

Candida albicans is a type of yeast (fungus) that is a common infection in the mouth. Usually, it is not a serious infection. It can be troublesome, but is usually easily treated. It likes to infect moist places such as the mouth (although it can also affect wounds and the genitals). The mouth infection is called oral candidiasis (or oral thrush). It is called thrush because it can have white spots like the thrush's (bird's) chest.

Thrush can appear throughout the mouth as thick white or red patches. It can cause discomfort but is mostly asymptomatic.

Why have I got oral thrush?

The candida fungus is often present in your mouth. However, under some conditions, it can overgrow to produce symptoms - this is when the balance in the mouth is tipped in favour of the candida growing. This overgrowth is often linked to a change in the immune system of the person but it can also be linked to other local changes in the mouth that encourage its growth.

What types of people often get candida infection?

Candida is more common in people who have a reduced immunity or who have local changes in their mouth that favour its growth including:

  • The very young because their immune system is still developing

  • Pregnant women because of normal hormonal changes

  • The elderly because their immune systems can be suppressed.

  • People who have diabetes (because of changes in the tissues of the mouth)

  • People who have infections that depress the immune system (eg HIV/AIDS).

  • People who are having treatments that reduce their immunity (eg transplant patients, some cancer patients, some asthmatic people who are taking higher-dose steroids).

If I have candida, what should I do?

Candida can be without obvious symptoms, and your dentist or doctor might find it as part of a routine checkup. It can also give you a sore mouth and your doctor or dentist might want to scrape a little from your mouth (or take a culture swab) and look at it under the microscope.

If you are in one of the groups of people at increased risk (see above), you doctor (or dentist) will usually be on the look out for candida infection. Treatment is with the use of antifungal tablets. Mouthwashes such as those containing chlorhexidine are also helpful.