Milia occur in 40% of infants as 1-mm-diameter papules scattered over the forehead, nose, and cheeks. They are caused by superficial epidermal cysts. Epstein pearls are milia that occur in the oral cavity. Milia and Epstein pearls rupture spontaneously and disappear. Acne neonatorum, or acne in infants, may occur when the infant is 4 to 6 weeks old and may persist for 6 months to a year until spontaneous resolution occurs.

Erythema toxicum occurs in up to 50% of all full-term infants 24 to 48 hours after birth. It presents as blotchy red macules usually on the chest, back, face, or, less commonly, the extremities. Usually, the macules begin to fade in 1 to 2 days and are gone by 1 week. Although serum eosinophilia may occur, the macules are not caused by microorganisms.