Thrush, or oropharyngeal candidiasis, is a common infection in babies. It is a fungal infection caused by Candida that affects the mouth and throat.

Candida is found on the skin and in the body and usually does not cause any infections.  But sometimes a baby can end up with thrush because they do not have a strong immune system yet.

Signs and Symptoms of Thrush 

The most common sign of a thrush infection is white plaques on the tongue, inside of the cheeks or on the roof of the mouth.  The plaques cannot be easily wiped off.

Sometimes the mouth can become painful and cause infants to refuse to eat and swallow because of the pain.  

Occasionally, the baby may also have a Candida infection in the diaper area as well.

Breastfeeding mothers may also have a Candida infection of the nipples.  They may complain of sore nipples or burning or shooting pain in the breasts.

What Should I Do If I Think My Baby Has Thrush?

If you think your baby has thrush, they should be evaluated by their primary health care provider to determine if they require antifungal treatment.  

All pacifiers, bottles and nipples, and toys should be washed with hot soapy water between uses to prevent a recurring infection.

Breastfeeding mothers may also require topical antifungal treatment to prevent an infection from being passed back and forth.  

Treatment of Thrush

The most common prescription medicine for treatment of thrush in an infant is nystatin.  Your primary health care provider will determine if this is the right medicine for your baby.  

Symptoms usually start to improve within 2-3 days of starting nystatin.  Treatment is usually 7-14 days total.  You should make sure you finish the full course of treatment prescribed even if the white plaques are gone.  

Breastfeeding may continue during treatment of thrush, unless you are otherwise directed not to do so.  

This post was co-authored by Erin Manchuk, BScPharm, BCGP and Stephanie Liu, MD, MSc, CCFP, BHSc.