Oral thrush is an infection of the mouth caused by a yeast fungus known as candida. More than half of the population will have candida present in their mouth without experiencing any ill effects.
Candida can cause problems when there is a change in the chemicals inside the mouth, which wipes out the good bacteria and allows the yeast fungus to grow and develop.
Oral thrush is common in people:
- with diabetes
- with chronic medical conditions like cancer or untreated HIV
- taking antibiotics (especially for long periods of time)
- who are dependent on drugs
- who eat a poor diet (malnutrition)
- who wear dentures (especially if they do not fit well)
Oral thrush can also be a side effect of inhaled corticosteroids, a type of medication for asthma.
Oral thrush symptoms
Oral thrush causes white patches in the mouth that can be wiped away, leaving red and bleeding areas. Other symptoms include:
- pain and burning in the mouth
- an unpleasant taste
- not being able to taste properly
- a red mouth and throat
- cracks at the corners of the mouth
- not being able to eat or drink properly
Oral thrush treatment
You may require an antifungal medication or lozenge to clear the infection. You can speak to your pharmacist about the best treatment.
Speak to your doctor if the thrush is severe or comes back after treatment.
Looking after your mouth
- Brush your teeth after each meal with fluoride toothpaste to reduce the build-up of bacteria in your mouth.
- Use a soft toothbrush if your mouth is painful.
- If you wear dentures, ensure they are cleaned properly and that the skin under the dentures is also clean. Rinse your mouth out after every meal.
- If you use inhaled corticosteroids, rinse your mouth thoroughly with water after each inhalation.
- Drink water unless you have an existing medical condition which means this is not possible.
- Smoking can also make symptoms worse. If you smoke, try to cut down or quit smoking.
Not sure what to do next?
If you are still concerned about your oral thrush, check your symptoms with healthdirect’s online Symptom Checker to get advice on when to seek medical attention.
The Symptom Checker guides you to the next appropriate healthcare steps, whether it’s self care, talking to a health professional, going to a hospital or calling triple zero (000).
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Last reviewed: December 2019