What Is Thrush in Babies?

Look for velvety, white patches in your baby’s mouth

Thrush is a type of fungal infection caused by the Candida yeast, the same fungus responsible for yeast infections. Thrush, also known as oral candidiasis, occurs in the mouth and presents as white patches on the inner cheeks, tongue, and top of the mouth.

Thrush in babies refers to a yeast infection in an infant’s tongue and mouth. It is a common condition among infants and young children. 

Thrush may also cause redness, pain, loss of taste, and dry mouth. Thrush in babies occurs when the normal yeast that lives on the skin multiplies and overgrows in the mouth. Babies younger than 1 month old are especially at risk of having thrush. 

geographic tongue, white tongue symptoms, thrush in young children

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Types of Thrush in Babies

While we typically think of thrush as occurring in the mouth, it can also affect the following body parts:

  • Fingernails 
  • Eyes
  • Diaper area (the vagina or groin)
  • Skin folds (armpits or folds in the neck)

Thrush Symptoms in Babies

The classic sign of thrush in babies is white, velvety patches over their tongue and inner cheeks. These patches are sores and may bleed when wiped. Other symptoms include:

  • Redness in the mouth
  • Crying or fussiness
  • Refusing to nurse due to pain

When thrush spreads down your baby’s esophagus, swallowing may become painful. You may notice that your little one refuses the bottle or nursing, as well as the pacifier.

If the yeast enters a baby’s digestive tract and their stool, it may lead to a yeast infection in the diaper area as well. If you notice that your baby has a diaper rash at the same time that they have thrush, they may be experiencing another yeast infection.

A mother will also experience symptoms if she has a yeast infection on her nipples. A mother who is breastfeeding may experience a yeast infection on her nipples due to her child’s thrush, or the thrush could be a result of the mother’s infection.

Frequent signs include nipples that are darker in color, cracked, and sore. She may also experience pain with breastfeeding. This infection requires treatment from your doctor.

A white tongue alone does not mean that your baby has thrush. Many babies have white tongues after drinking milk. The white patches from thrush usually cover multiple surfaces in your child’s mouth and cannot be easily wiped away. When you attempt to wipe them away, the sores may bleed.

Causes

Thrush occurs when the yeast Candida albicans begins growing out of control in a baby’s mouth. Yeast thrives in warm, moist places, such as a baby’s mouth. The type of yeast that causes thrush usually lives on our skin and in our bodies without causing issues. However, once the yeast begins to overgrow, an infection can occur.

The most common cause of thrush in babies is related to a nursing mother’s antibiotic use. Antibiotics kill the good bacteria in our bodies that usually keep yeast from overgrowing. Once these bacteria die off, the yeast can grow at an out-of-control rate. This is why it’s common for women to experience a vaginal yeast infection while taking antibiotics.

When a nursing mother takes antibiotics, she is at risk of experiencing a yeast infection of her nipples. Once this happens, it’s likely that the infection will pass on to the baby’s mouth during feedings. Also, if your baby requires antibiotic therapy, they may develop thrush.

A less common cause of thrush in babies can occur during childbirth. If a mother has a vaginal yeast infection, the baby may become infected during labor and delivery. 

Diagnosis

Fortunately, thrush is quick and simple to diagnose. Most pediatricians can identify it by looking in your baby’s mouth. The velvety, white patches that cannot be wiped away are classic signs of thrush. Occasionally, your doctor may recommend scraping off a sample of the white patch for lab testing.

When to See the Doctor

It’s important to see your pediatrician any time you suspect your baby has thrush. Talk with your doctor right away if your baby is refusing to eat or becomes inconsolable. If your baby is refusing to eat, be on the lookout for signs of dehydration. Monitor how many wet diapers your child has, and call your pediatrician if you are concerned.

Treatment

Thrush does not always require treatment and sometimes goes away on its own after a few days. It is still beneficial to see your pediatrician to make sure that the sores in your baby’s mouth are caused by thrush and not another infection.

Your pediatrician may prescribe an antifungal medication to treat your child’s infection. This medication can be painted onto the sores in your baby’s mouth. If the mother has a yeast infection on her nipples as well, her doctor will most likely recommend an over-the-counter antifungal cream to be applied directly to the nipples. The doctor could also recommend an oral antifungal prescription such as Diflucan (fluconazole). 

Most cases of thrush in babies resolve within two weeks of starting treatment.

Taking a regular probiotic may help prevent thrush and other types of yeast infections. Probiotics help support the good bacteria on your skin and in your body, which keep yeast growth under control. A 2016 study found that taking a probiotic supplement may help treat and prevent Candida infections. Talk with your pediatrician before beginning a supplement regimen for your infant. If you are breastfeeding, hold off on starting any natural remedies until you’ve talked with your doctor. 

Prognosis

Thrush is a common infection in babies and is usually easy to diagnose and treat. If both you and your baby are experiencing a yeast infection at the same time, be sure to have both infections treated right away. If only one of you is treated, it’s likely that you will continue to pass the infection back and forth each time you breastfeed. 

If you notice that your baby is getting frequent thrush infections, talk with your pediatrician to find out if further testing is needed. 

Thrush is not preventable, but you can take steps to reduce your baby’s risk. Be sure to thoroughly clean and sterilize anything that goes into your baby’s mouth, such as a pacifier or bottle nipple. Change your baby’s diaper often to help prevent a yeast infection in their diaper area. If you are currently breastfeeding and suspect you may have a yeast infection on your nipples, talk with your doctor right away to begin treatment and prevent the spread to your baby. 

A Word From Verywell

If you suspect that your baby may be experiencing thrush, talk with your pediatrician. The most common sign to look for is white patches inside the mouth.

Thrush in babies is most often related to breastfeeding and can be treated with antifungal medication. See your pediatrician if your child is experiencing pain and is unable to eat due to the infection.

While it is upsetting to see your child uncomfortable, remember that thrush is a common condition in infancy and usually clears up quickly with treatment. 

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Article 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.
  1. Centers for Disease Control and Prevention. Candida infections of the mouth, throat, and esophagus. Updated February 25, 2021.

  2. MedlinePlus. Thrush in newborns. Updated May 4, 2021.

  3. American Academy of Pediatrics. Thrush and other Candida infections. Updated October 21, 2020.

  4. Seattle Children’s. Thrush. Updated April 27, 2021.

  5. Matsubara VH, Bandara HM, Mayer MP, Samaranayake LP. Probiotics as antifungals in mucosal candidiasis. Clin Infect Dis. 2016;62(9):1143-53. doi:10.1093/cid/ciw038

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