As allergists, we see many patients with rashes of all types. There are many different causes of rashes, and one type has been in the news lately–a preservative found in many popular wet wipes and baby wipes has been determined as the cause of allergic contact dermatitis in some children. Allergic contact dermatitis is caused by exposure to a substance or material to which the patient has become extra sensitive or allergic. Although a reaction to a substance may not first happen when the patient is first exposed to it, regular use can eventually cause sensitivity and a skin reaction to the product.