Wet, soiled diapers that rub against delicate baby skin and misuse or overuse of baby creams, lotions, oils, and powders are the culprits behind diaper rash, a red, inflamed rash that affects most babies at least once during their infancy. It can also be a recurrent problem for newborns and can become so severe that open, blistering sores develop on babies' thighs, abdomens, and buttocks. Wet nappies, as the British call them, create a humid, moist environment that makes babies' bottoms susceptible to irritation and inflammation. The solution: change diapers frequently, and gently cleanse-don't rub-the baby's buttocks with a warm, wet washcloth. Then apply a protective cream that contains zinc oxide to provide a barrier against urine and feces. (Zinc oxide creams are available without a prescription.) Avoid pre-moistened baby wipes and products that contain fragrances or alcohol, which may actually make diaper rash worse rather than better because they may irritate a baby's delicate skin. Also, after washing the baby's bottom, allow the buttocks to air dry for a few minutes before putting on a new diaper.