What is Oral Thrush?
Oral thrush is a very common infection in infants that causes irritation in and around the baby's mouth. It is caused by the overgrowth of the yeast candida albicans.
Most people (including infants) naturally have candida in their mouths and digestive tracts. The amount of candida in a person's body is controlled by a healthy immune system and some "good" bacteria. If the immune system is weakened (due to an illness or medicines like chemotherapy), the candida in a person's digestive tract can overgrow and lead to an infection. The same can happen to infants whose immune systems are not yet fully developed.
Sometimes candida overgrowth occurs after a baby has received antibiotics for a bacterial infection, because antibiotics can kill off the "good" bacteria that keep the candida from growing. Candida overgrowth can lead to vaginal (yeast) infections, diaper rashes, or oral thrush.
Oral thrush can affect anyone, although it's most common in infants younger than 6 months and in older adults. A baby with oral thrush might develop cracked skin in the corners of the mouth or whitish patches on the lips, tongue, or inside the cheeks that look a little like cottage cheese but can't be wiped away. Many babies don't feel anything at all, but some may be uncomfortable when sucking.
Preventing and Treating Oral Thrush
There's not much that you can do to prevent your infant from getting oral thrush. Most cases go away without medical treatment within a week or two, but your doctor may prescribe an antifungal solution for your baby's mouth. And depending on your baby's age, the doctor may also suggest adding yogurt with lactobacilli to your child's diet. The lactobacilli are the "good" bacteria that can help eliminate the yeast in your child's mouth.
If you are formula-feeding your baby or using a pacifier, it's important to thoroughly clean the nipples and pacifiers in hot water after each use. That way, if there's yeast on the bottle nipple or pacifier, your baby doesn't continue to get reinfected.
If you are breastfeeding and your nipples are red and sore, there's a chance you may have a yeast infection on your nipples, and that you and the baby are passing it back and forth. If so, you may want to talk to the doctor about using an antifungal ointment on your nipples while the baby is being treated with the antifungal solution.
If your child keeps getting oral thrush, especially if he or she is older than 9 months, talk with your doctor because this might be an indication of another health issue.
Reviewed by: Elana Pearl Ben-Joseph, MD
Date reviewed: December 2008
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