Erythema toxicum — also called erythema toxicum neonatorum (ETN) or toxic erythema of the newborn — is a common rash seen in full-term newborns. It usually appears in the first few days after birth and fades within a week.
Up to half of all newborns will have ETN. The rash can be on the baby's face, chest, arms, and legs, but usually won't be on the palms or soles of the feet. It's a blotchy red rash with small bumps that can be filled with fluid. Although the fluid might look like pus, there is no infection.
Because erythema toxicum doesn't cause any symptoms and goes away on its own, no treatment is needed.
Follow your doctor's advice about caring for your baby's skin. Call your doctor if your baby has a rash and is also fussy, not feeding well, or has a fever.