by EBSCO Medical Review Board
(Oral Candidiasis—Adult)

Definition

Thrush is an infection inside the mouth. It usually begins on the tongue and inside of the cheeks. It can spread to the roof of the mouth, gums, tonsils, and throat.

Thrush
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Causes

This health problem is caused by yeast, a type of fungus. It is normally found in the mouth in small amounts. It can cause symptoms when too much of it grows and spreads.

Risk Factors

This problem is more common in babies and older adults. Other things that may raise the risk are:

  • Having a weakened immune system due to health problems like HIV
  • Taking certain medicines, such as corticosteroids and antibiotics
  • Poor nutrition
  • Eating a diet rich in carbohydrates
  • Pregnancy
  • Wearing devices in the mouth, such as dentures
  • Thumb sucking
  • Endocrine problems, such as diabetes, Cushing disease, and thyroid issues
  • Cancer and cancer treatment
  • Smoking

Symptoms

Some people may not have symptoms. Those who do may have:

  • White patches on the inside of the cheeks, tongue, roof of mouth, and throat
  • Redness and soreness
  • Pain when eating or swallowing
  • Loss of taste
  • Cracking and redness at the corners of the mouth

Diagnosis

The doctor will ask about your symptoms and health history. A physical exam will be done. It will focus on the mouth. This is often enough to make the diagnosis.

If the cause is not clear, a sample of cells may be taken from the mouth for testing. This can be done with an oral swab, scraping, or rinse.

Treatment

The goal of treatment is to restore the normal balance of yeast in the mouth. Any underlying causes will also be treated.

Choices are:

  • Antifungal medicine
  • Supportive care, such as good oral hygiene and denture care

Prevention

The risk of this health problem may be lowered by:

  • Managing underlying health problems
  • Practicing good oral hygiene

RESOURCES

Centers for Disease Control and Prevention  https://www.cdc.gov 

National Foundation for Infectious Diseases  http://www.nfid.org 

CANADIAN RESOURCES

Canadian Dental Association  http://www.cda-adc.ca 

Public Health Agency of Canada  https://www. canada.ca 

References

Candida infections of the mouth, throat, and esophagus. Centers for Disease Control and Prevention website. Available at: https://www.cdc.gov/fungal/diseases/candidiasis/thrush/index.html. Accessed March 25, 2021.

Dentures. Mouth Healthy—American Dental Association website. Available at: http://www.mouthhealthy.org/en/az-topics/d/dentures. Accessed March 25, 2021.

Lewis MAO, Williams DW. Diagnosis and management of oral candidosis. Br Dent J. 2017 Nov 10;223(9):675-681.

Oral candidiasis. EBSCO DynaMed website. Available at: https://www.dynamed.com/condition/oral-candidiasis. Accessed March 25, 2021.

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