Oral Thrush

What is Oral Thrush?

Oral thrush, also called oral candidiasis, is an infection of the mouth caused by the candida albicans fungus – better known by its common name of yeast. Besides the mouth, the same fungus can cause vaginal yeast infections in women and diaper rash in infants. Oral thrush is most commonly seen in older adults, babies and toddlers, patients who use steroid sprays to treat asthma, and those with weakened immune systems due to other conditions like HIV, cancer, and diabetes.

The fungus is always present in small amounts within the mouth, skin, and digestive tract of healthy individuals and is normally kept under control by other microorganisms and bacteria. Events such as stress, illness, and the use of medications like birth control pills and corticosteroids can occasionally disrupt that balance in such a way that the candida fungus is allowed to grow unchecked, which leads to the development of oral thrush.

What are the Symptoms of Oral Thrush?

Symptoms of oral thrush can develop slowly or set in without warning, and they can last for only a few days or several months. The most common complaint from patients is white sores on the inner cheeks or tongue that resemble cottage cheese. Other common symptoms include:

  • Pain when swallowing
  • Burning mouth
  • Dry mouth
  • Bad breath
  • White tongue
  • Changes in sense of taste
  • Bleeding if lesions are scraped
  • Redness or cracking at corners of mouth

In severe cases, lesions can work their way into the esophagus. This can result of a constant feeling of food stuck in the throat. Infants with the condition may become irritable and fussy or have difficulty feeding. The infection can be passed back and forth between mothers and their children while breastfeeding.

Oral Thrush Causes

Oral thrush is caused by a species of yeast or fungus known as Candida albicans. Candida is usually present in the mouth in small quantities along with a variety of good bacteria. Usually, each type of the bacteria keeps the other in check.

  • A balance upset of oral bacteria clears the way for the yeast to grow, eventually resulting in thrush. White bumps on the inner cheeks and tongue are a sign of thrush.
  • Similarly, oral thrush usually occurs when the immune system is destabilized by some medications that decrease the number of useful microorganisms that naturally halt infections.
  • Cancer treatments such as radiation and chemotherapy also destroy healthy cells, making people more vulnerable to oral thrush.
  • Diseases such as leukemia, diabetes, and HIV/AIDS attack the immune system thus increasing the risk of oral thrush. It is understood that C. albicans can use the extra sugar to enhance its growth in the mouth.
  • Newborns can contract oral thrush at birth since the fungus that causes oral thrush also causes yeast infections. Pregnant women with vaginal yeast infection, therefore, pass the infection on to their baby during delivery.

How is Oral Thrush Treated?

The goal of treatments for oral thrush is to stop the infection from spreading. To do this, patients are often prescribed about two weeks’ worth of antifungal medications. Improved dental hygiene habits can improve the condition and help prevent future occurrences.

Oral Thrush Prevention

To prevent oral thrush, the following precautions should be taken:

  • Good oral hygiene is critical and can be achieved by brushing the teeth twice a day. Flossing teeth should also be done daily. It is particularly essential if one wears dentures or has diabetes
  • Persons who previously had an oral thrush should replace their toothbrushes.
  • After using a corticosteroid inhaler, a person should thoroughly rinse out the mouth.
  • Whenever one is taking prescribed antibiotics, yogurt should be added to the diet since it has beneficial bacteria that will help fight the growth of the unwanted bacterium that causes oral thrush.
  • A vaginal yeast infection should be treated promptly especially during pregnancy to avoid infecting an unborn baby.
Last Reviewed:
October 07, 2016
Last Updated:
January 18, 2018