Everything You Need to Know About Thrush

Thrush is a yeast infection caused by the Candida fungus. It affects areas in a person’s mouth, tongue, and throat. The most common culprit is Candida albicans.

Though anyone can develop thrush, it most commonly occurs in newborns and older adults. Individuals who have weakened immune systems or are taking certain medications are also at risk. Most of the time, thrush can be treated easily with antifungal medicines.

People with thrush sometimes develop Candida infections in other body areas, such as the vagina or esophagus. However, the term thrush describes mouth and throat Candida infections.

This article discusses the symptoms, causes, and treatment options for thrush.

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Thrush in the mouth

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Types of Thrush

There are two types of thrush:

  • Pseudomembranous: The most common type that appears as white patches on the tongue, mouth, or back of the throat.
  • Atrophic: Less common and usually affects older adults. It generally appears as red patches under the upper dentures.

What Are the Symptoms of Thrush?

Some symptoms of thrush may include:

  • A cottony feeling in your mouth
  • White or red patches inside the mouth or the back of the throat
  • Pain when swallowing or eating
  • Sensitivity to spicy foods
  • Loss of taste
  • Bleeding when brushing teeth
  • Cracking at the corners of the mouth

However, some people with thrush don’t develop any symptoms.

What Does Thrush Look Like?

Classic thrush lesions are typically white, raised, and may look like cottage cheese. 

What Causes Thrush?

Thrush happens when Candida yeast, which usually lives in the mucous membranes of the mouth and throat, grows out of control. Stress, different illnesses, and certain medicines can disrupt the balance of yeast and cause the fungus to multiply.

Antibiotics are one common trigger for thrush. These medicines can eliminate normal bacteria in your mouth, which allows fungus to build up. Birth control pills and steroids may also prompt yeast to grow and increase your chances of developing thrush.

Other risk factors for thrush may include:

  • Babies and older people are more likely to develop thrush
  • Poor health
  • A medical condition that comprises your immune system, such as AIDS or HIV
  • Medication that weakens your immune system, such as chemotherapy
  • High blood sugar levels
  • An organ transplant recipient
  • Dentures that don’t fit correctly
  • Dry mouth

What Conditions Are Similar to Thrush?

Some conditions that may be mistaken for thrush include:

  • Leukoplakia: It causes thick, white patches to form in the mouth.
  • Geographic tongue: An inflammatory condition that affects the surface of the tongue.
  • Canker sores: They are painful ulcers that form in the mouth.
  • Oral lichen planus: A chronic, inflammatory condition that affects the mucous membranes in the mouth.

Is Thrush Contagious?

Thrush is generally not considered contagious. However, it can spread from one person to another among those who are at high risk. For instance, people with weakened immune systems, babies that breastfeed, or those who take certain medicines may be more susceptible when exposed to the infection.  

Thrush in Babies

Because infants don’t have fully mature immune systems, thrush is more likely to affect them. The infection may occur when a mother or baby takes antibiotics. Or, when a baby breastfeeds, the mother’s nipples can harbor yeast.

How to Calm a Baby with Thrush

Too much sucking can irritate a baby's mouth. Try to limit feedings to 20 minutes and minimize pacifier sucking.

When to See a Healthcare Provider for Thrush

You should see your healthcare provider if you or your baby develops symptoms of thrush, especially if you have a medical condition or take a medicine that suppresses your immune system.

How Is Thrush Diagnosed?

Healthcare providers typically diagnose thrush by examining lesions inside a person’s mouth. They may scrape a small sample from the sore to examine it under a microscope.

How Is Thrush Treated?

Thrush is typically treated with prescription antifungal medicines, such as

  • A mouthwash that contains nystatin
  • Lozenges that contain clotrimazole
  • Pills or liquids that contain Diflucan (fluconazole) or Sporanox (itraconazole)

Can Thrush Go Away on Its Own?

Thrush often goes away on its own without any treatment.

How to Prevent Thrush

You may prevent thrush by:

  • Practicing good hygiene: Rinse your mouth after meals, brush your teeth and gums twice a day, floss regularly, and replace your toothbrush often to avoid harmful germs.
  • Taking acidophilus pills or eating yogurt: These can help balance the good and bad germs in your mouth. 
  • Taking care of dentures: Remove and clean dentures every night if you wear them.
  • Quitting smoking.
  • Keeping blood sugar levels controlled if you have diabetes.
  • Using antibiotics sparingly.
  • Cleaning and disinfecting all bottles and pacifiers that babies use.

Can Thrush Spread?

If left untreated, thrush can sometimes spread throughout the body and affect your:

  • Esophagus
  • Eyes
  • Brain
  • Heart
  • Joints


With proper treatment, thrush usually clears within a couple of weeks. However, if symptoms persist, let a healthcare provider know. Thrush is typically easy to treat but can become serious if it spreads. Additionally, some people develop chronic thrush, which is more common if they have a weakened immune system or another underlying health problem.

7 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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  2. Patil S, Rao RS, Majumdar B, Anil S. Clinical appearance of oral Candida infection and therapeutic strategiesFront Microbiol. 2015;6:1391. doi:10.3389/fmicb.2015.01391

  3. American Academy of Family Physicians. Thrush.

  4. MedlinePlus. Thrush - children and adults.

  5. Seattle Children's. Thrush.

  6. National Library of Medicine. Oral thrush: Overview.

  7. National Institute of Diabetes and Digestive and Kidney Diseases. Clotrimazole.