Hives are a form of skin rash that comes suddenly and disappears without leaving a trace. Hives are usually a reaction to histamine, a substance in the body that often causes allergy. The rash consists of white or red wheals (raised patches) that itch. Hives may be caused by a variety of substances to which the sufferer is allergic or hypersensitive. A person may be allergic to a food or drug, or to a substance that is inhaled, such as dust or pollen. Patients also may become allergic to a substance after they come in contact with it. For example, people may become allergic to chemicals they touch frequently or to an animal’s fur. An outbreak of hives often may be treated with antihistamine drugs or by bathing the spots with lotions of baking soda and water, witch hazel, or some other cooling solution.
Hives are also known as nettle rash. The medical name for hives is urticaria.
