Yeast naturally lives on the surface of nipples, in balance with the bacterial microbiome. Several factors might affect this balance, such as antibiotics given for Group B strep or cesarean birth. Symptoms are usually bilateral, and the regions of the nipple/areola complex taken in orally by the infant are typically bright red. The pain is described as “hot” or “burning”. A gram stain and /or culture should be done to differentiate this from dermatitis. Yeast can be treated with a topical antifungal such as 1% clotrimazole cream twice a day or nystatin ointment 4 times a day (do NOT use the infant oral drops on maternal nipples!). Oral fluconazole can also be used, 200mg once a day for 7-10 days. If the infant has visible oral thrush, the infant should also be treated with an anti-fungal medication, such as oral nystatin suspension 1-2 ml into each cheek 4 times a day or fluconazole suspension 6mg/kg po day 1 then 3mg/kg daily for another 6-13 days.