Why do nipples itch while breastfeeding?

Different things: It could be dermatitis or yeast from staying wet much of the time. You can air dry them between feedings or use nipple shields that keep them from direct contact with wet clothing. You can find those at a breastfeeding supply store. You can put lotrimin (clotrimazole) af cream on them 3 times a day for a week to clear up yeast. You just wipe off any excess before feeding, but don't worry about a small amount.