Oral Thrush: Causes, Symptoms, and Treatment

Medically Reviewed by Poonam Sachdev on October 03, 2023
7 min read

Thrush is an infection caused by the candida fungus, which is a type of yeast. You can get it in your mouth and sometimes other parts of the body. If you notice strange white bumps inside your mouth, it might be oral thrush. It’s also called oral candidiasis. 

Anyone can get thrush, but it happens most often to babies and toddlers, older people, and those with weakened immune systems.

Small amounts of the candida fungus are found naturally in your mouth, digestive tract, and skin. It’s usually kept under control by other bacteria. But certain medications and illnesses can upset the balance and cause the fungus to grow out of control.

One example is antibiotics. When you take them, they can kill the normal bacteria in your mouth, leaving candida fungus to multiply at will. 

Stress can cause it. So can other medicines and illnesses, including: 

Is thrush contagious?
Thrush the infection doesn’t spread from person to person, but the candida fungus can be transmitted to you if you come in contact with it in another person’s saliva. So if you kiss your partner and they have thrush, the fungus could get transmitted to your mouth. Whether you get thrush depends on your health and risk factors.

Thrush in pregnancy

You're more likely to get thrush when you're pregnant because of all of the hormonal changes. Your newborn could be more likely to get thrush, too, because they don't have a mature immune system, which makes it easier for the yeast to grow. 

But your baby could catch oral thrush if you’re breastfeeding. Your nipples provide the yeast the warm, moist spots to thrive, as does your baby's mouth. If you get nipple thrush, it can cause:

  • Red, sensitive, cracked, or itchy nipples
  • Shiny or flaky skin on your areolas, the areas around your nipples
  • Discomfort while nursing or tender nipples between feedings
  • Stabbing pains deep in the breast

You and your baby need to be treated for thrush or you could keep passing it back and forth.

Other things that can disrupt the normal balance of bacteria in your mouth and increase your chances of getting thrush include:

  • Uncontrolled diabetes
  • Cancer
  • Smoking
  • Dentures
  • An organ transplant
  • Chemotherapy or radiation

Age also is a risk factor. Older people and infants are more likely to get thrush.

If you have thrush, you may notice these signs:

  • White or red patches inside your mouth, on your tongue, and on the back of your throat
  • Raised spots that look like cottage cheese
  • Cracking and redness at the corners of your mouth (angular cheilitis)
  • A cottony feeling in your mouth
  • Loss of taste

Sometimes thrush may also cause:

  • Redness, irritation, and pain under your dentures (denture stomatitis)
  • A large red, painless mark in the center of your tongue (median rhomboid glossitis)
  • A band of gum irritation or inflammation (linear gingival erythema)

 In very bad cases, thrush can spread into your esophagus and cause:

  • Pain when you swallow or trouble swallowing
  • A feeling that food is stuck in your throat or in the middle of your chest
  • Fever, if the infection spreads beyond your esophagus

The fungus that causes thrush can spread to other parts of the body, like the lungs, liver, and skin. This happens more often in people with cancer, HIV, or other conditions that weaken the immune system.

What does oral thrush look like?

The appearance of oral thrush depends on which type you have:

  • White type (pseudomembranous) is the most common. Its symptoms include a white tongue coated with creamy lesions. You can probably wipe them off, but this might cause bleeding.
  • Red type (erythematous) usually shows up as a red and raw outline around dentures.
  • Hyperplastic (plaque-like candidiasis) shows up as solid white plaques on your tongue and mouth that can't be wiped off. It's not common and is most likely to affect people with HIV.

Is oral thrush painful?

You might find the sores from thrush painful, especially if you scrape them and cause them to bleed. Some people don't have any discomfort from the raised spots, but do have overall mouth soreness.

Your doctor can tell if you have thrush by looking inside your mouth for the white spots and creamy lesions. They might take a scrape of a lesion to send to a lab to confirm it's thrush. 

If it looks like the candida fungus has spread to your esophagus, your doctor might perform more tests, like: 

  • A throat culture (a swab of the back of your throat)
  • An endoscopy of your esophagus, stomach, and small intestine
  • X-rays of your esophagus


Oral thrush is usually easy to treat in healthy children and adults. But the symptoms may be harder to treat in people with weakened immune systems.

Thrush is treated with antifungal medications. Your doctor will probably prescribe a medicine you use in your mouth for 7-14 days. 

Does oral thrush go away by itself?

Thrush can sometimes clear up on its own, but it depends on how severe it is. 

Medications for thrush

The most common include: 

  • Clotrimazole (Mycelex Troche)
  • Miconazole (Oravig)
  • Nystatin (Bio-Statin)

If you have a serious infection, your doctor may treat you with the antifungal medication fluconazole (Diflucan), either orally or by IV.

How long does thrush last?

Thrush usually responds well to medications in healthy children and adults. It should clear up in a few weeks after you start treatment. But it could take longer in people who aren't as healthy.



Practicing good oral hygiene, like regular brushing and flossing, for several weeks might clear up oral thrush.

Other home remedies you can try to improve your symptoms include:

  • Rinse your mouth with 1/2 teaspoon of salt dissolved in a cup of warm water.
  • Gargle 1/2 teaspoon of baking soda dissolved in a cup of warm water.
  • Try foods and beverages with "good bacteria" (probiotics), like yogurt, kombucha, or kefir, to restore the balance of yeast in your mouth.
  • Rinse with 1 teaspoon of apple cider vinegar mixed with a cup of water, then spit out.
  • If you wear dentures, disinfect them as your dentist recommends.

Home remedies for thrush in babies

If your baby has oral thrush, it might clear up on its own. You should avoid any type of home remedy without discussing them with your child's pediatrician first. 

There are several things you can do at home to help prevent your newborn from getting oral thrush: 

  • Wash your hands before and after you touch their mouth. 
  • Sterilize their bottle nipples after you use them in boiling water for 10 minutes.
  • Sterilize their pacifiers the same way, and don't let anybody put your child's pacifiers in their mouth.
  • If you're breastfeeding, clean your breasts every time you feed your baby, using water. Let them air-dry.
  • Keep feeding sessions to 20 minutes. Any longer can cause irritation to your baby's mouth.
  • If you're pumping, sterilize all parts of your pump after each use.
  • Be sure your child drinks plenty of liquids so they do not get dehydrated (lose too much fluid).

If you're healthy, it's unlikely you'll have complications. But in rare cases, the candida fungus can get into your bloodstream and other parts of your body, including your brain and heart. 

This can cause septic shock, a life-threatening condition that happens when your blood pressure drops dangerously low after an infection.

Here are ways to reduce your chances of getting oral thrush:

  • Brush your teeth at least twice a day and floss at least once.
  • Get regular dental checkups, especially if you have diabetes or wear dentures. 
  • Treat chronic health issues, and take your medications as they're prescribed.
  • Don't overuse mouthwashes or sprays, which can upset the normal balance of bacteria in your mouth.
  • Clean your inhalers after each use to kill germs, and rinse your mouth afterward. 
  • Limit foods that contain sugar and yeast. 
  • Don't smoke, vape, or use tobacco products. 
  • Make sure your dentures fit correctly. Remove them at night and clean them daily.

Oral thrush is an infection of your mouth caused by the candida fungus. Toddlers and children get it most often, but anyone can get thrush. It happens when the normal level of bacteria in your mouth gets out of balance, usually from something like an illness or a medication. Thrush causes creamy white lesions on your tongue and mouth that are usually treated with antifungal medications.

What does oral thrush feel like?

Sometimes, people with oral thrush don't have any symptoms at all. But you could have a burning sensation, loss of taste, dry mouth, and pain when you swallow or trouble swallowing.

Why do I suddenly get oral thrush?

Symptoms of oral thrush can develop slowly or rapidly, but the cause is the same: Something has upset the balance of normal bacteria in your mouth and allowed the candida fungus to grow out of control.