Hives, or urticaria, are a common skin rash that appears as raised, itchy welts. Sometimes, hives resolve quickly on their own, but if they persist, over-the-counter medications often help. Hives ...

A 32-year-old woman presents to the emergency department for evaluation of a worsening rash that begins at her navel and continues down both of her legs. The rash first appeared approximately 10 days ...