Oral Thrush (Oral Candidiasis)

Understand oral thrush, and its causes and symptoms.

Oral Thrush (Oral Candidiasis)


Oral thrush, also known as oral candidiasis, is a fungal infection of the mouth that may spread to your gums or tonsils, or the back of your throat.


Oral thrush is caused by an overgrowth of the usually harmless fungus called Candida (Candida albicans) in your mouth. The imbalance in Candida is usually triggered by:

  • Weakened immunity especially in newborns, older populations, people with cancer or with HIV/AIDS
  • Large amounts of sugar in your saliva as with uncontrolled diabetes
  • Vaginal yeast infections which can be passed to your baby
  • Medications such as antibiotics that can alter the natural balance of microorganisms in your body
  • Wearing dentures
  • Using asthma inhalers


Common symptoms of oral thrush to look out for are:

  • Creamy white patches on the tongue, inner cheeks, roof of the mouth (palate), gums, back of the throat and tonsils
  • Red, swollen or irritated lesions around the infected area
  • Cracked or red corners of your mouth
  • Difficult or painful swallowing and eating
  • Mild to moderate loss of taste
  • Pain under dentures (denture stomatitis)

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