What is Uticaria?
Hives are an intensely itchy rash that consists of raised, irregularly shaped wheals. The wheals have blanched center, surrounded by a red flare. Urticaria is caused by histamine released from dermal mast cells. Histamine release is most commonly causes by an immunologic reaction between antigens and IgE antibodies bound to mast cell membranes. Histamines cause increased vascular permeability. Antigens, chemicals and physical agents (Detergents or ultraviolet light) can cause urticaria.