Also called candidiasis, oral thrush is a common infant ailment that causes yeast to grow in and around a baby's mouth. Usually affecting infants younger than six months, oral thrush causes white cottage cheese-type patches to appear on the lips, tongue and inside the cheek. Many infants with thrush are symptom free while others appear uncomfortable when sucking. Thrush develops for a variety of reason, and most should not cause concern for parents or caregivers because the condition usually clears up with little or no treatment.
Infection
Most infants have the yeast known as candida present in the mouth and digestive tract, according to the KidsHealth website. When an infant is healthy, the immune system controls yeast growth. When an infant's immune system is immature due to premature birth or weakened by an infection, yeast can grow unchecked.
Breastfeeding
A newborn baby can develop thrush from breastfeeding when there is a yeast infection on the nipples, according to the Womens' Healthcare Topics website. Because nursing with thrush can become uncomfortable for the baby, many doctors prescribe an antifungal treatment known as Nystatin that kills thrush.
Parents should squirt Nystatin into the mouth four times a day, and dab larger patches with a cotton swab dipped in Nystatin. This treatment should work within two weeks time. To prevent thrush from making a comeback, mothers should let their nipples air dry between feedings, and wash breast pump parts in a solution of vinegar and water that prevents yeast growth.
Antibiotics
Oral thrush can grow after a baby has completed a course of antibiotics to treat an infection, according to KidsHealth. This occurs when antibiotics kill off the "good" bacteria used by the immune system to keep yeast in check. In addition to oral thrush, babies can develop related conditions like diaper rashes or vaginal yeast infections in baby girls.
