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
Most people (including infants) naturally have
in their mouths and digestive tracts. The amount of
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
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.
overgrowth occurs after a baby has received antibiotics for a
bacterial infection, because antibiotics can kill off the
"good" bacteria that keep the
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
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
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
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.
Elana Pearl Ben-Joseph, MD
Date reviewed: December 2008
Note: All information is for educational purposes only. For specific medical advice,
diagnoses, and treatment, consult your doctor.
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