ABSTRACT
Urticaria, derived from the Latin urere, to burn, describes an eruption of transient, circumscribed cutaneous swellings. The wheal or hive, an oedematous, erythematous papule or plaque, is the characteristic lesion in urticaria and is almost invariably itchy.1 Angio-oedema is considered part of the same disease process as urticaria, but involves deeper tissues.2 The swellings of angio-oedema are subcutaneous and usually also involve the mucous membranes, although they can occur anywhere on the body. Itching is variable and the swellings disappear in 24-72 hours. Angio-oedema may occur alone (11%), in combination with urticaria (49%), or urticaria may occur alone (40%).2
