Chronic urticaria is a well-known disease entity, characterized by the rapid appearance of frequently occurring, short-lived wheals, surrounded by a bright-red flare, and often accompanied by angioedema. Any pattern of recurrent urticaria occurring at least twice a week for 6 weeks is called chronic. The cause of chronic urticaria is undefined and its diagnosis requires exclusion of other conditions with somewhat similar symptoms. Degranulation of mast cells with release of histamine is central to the development of wheals. About 26~50% of patients with idiopathic urticaria have histamine-releasing autoantibodies in their blood. Urticaria has a profound impact on the quality of life. It is essential to avoid substances likely to trigger or intensify episodes. Treatment is directed at eliminating or at least substantially reducing symptoms. The most important pharmacotherapy is non-sedating H1 antihistamines. They have proved to be effective in double-blind controlled studies. However, alternative therapies may be required because of different urticaria subtypes and individual variations. Immunosuppressive drugs such as cyclosporin A and corticosteroids should not be used as a long-term management due to undesirable side effects.