Chronic Idiopathic Urticaria (CIU) is a condition characterized by the presence of hives, also known as urticaria, that persist for six weeks or longer without any identifiable cause. The term “idiopathic” means that the cause is unknown, and thus, the diagnosis is often made when other potential causes of chronic urticaria have been ruled out.

People with CIU experience recurrent episodes of hives, which are raised, itchy red welts on the skin. These hives can vary in size and shape and can appear anywhere on the body. The condition can significantly impact the quality of life due to the persistent itchiness and discomfort.