The yeast infection usually involves the inside of a baby’s cheeks and lips and occasionally the tongue. It appears as white, almost cottage cheese like patches, and is often visible when a baby is yawning or crying. A baby who only has a white tongue typically does not have thrush, but just a milk coated tongue (see if you can wipe some of the milk off of the tongue, as yeast is usually more adherent).

Thrush is fairly common as we all have yeast in our digestive tracts, and babies are often colonized with yeast as they travel through the birth canal. For unknown reasons, in some infants there is an overgrowth of yeast and thrush may develop. Many mothers feel guilty that they “gave their baby” a yeast infection. They worry that thrush has something to do with cleanliness (NOT) and somehow that maternal guiles thing is already beginning. (Dads have already cut to the chase and say, how do you treat it?!)

Thrush can happen to any infant. In a breast feeding baby it may also cause a mother to have inflamed and tender nipples, and the baby and mother actually pass the yeast back and forth during feeding (no guilt, as breastfeeding is good!)

In most babies thrush does not cause a lot of problems and may go away by itself. But if the infection becomes extensive it may become painful and cause an infant to be uncomfortable when nursing or taking a bottle. If you notice that your baby has white plaques in their mouth or under their lips it may be worth a phone call to your pediatrician. (This is not an emergency and can wait till office hours.)

There are several prescription preparations that may be used to treat thrush. The most common being Nystatin, which is a liquid medication that is given to the baby after they have been fed, and is squirted into the mouth on the inside of the cheeks, to treat the yeast infection.  It is also beneficial to treat a nursing mother’s nipples with an anti-fungal agent. I usually tell patients to use the medications for at least seven days or until the white patches have been gone for several days before stopping treatment. It is not uncommon to get thrush again, so don’t fret if your baby develops another infection, at least you know what it is and how to treat it.

A yeast infection in the mouth may often lead to a yeast infection in the diaper area (candidal diaper dermatitis), because as you know what goes in the mouth comes out in the poop. But that rash is for another day….

That’s your daily dose, we’ll chat again tomorrow.

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