Urticaria, also known as hives, is a skin reaction that causes itchy welts. It is a raised, itchy rash that appears on the skin and can range in size from a few millimeters to the size of a dinner plate. Hives can be caused by an allergic reaction to food, medicine, or other triggers such as heat, cold, or pressure. The welts that come with hives are caused by the release of immune system chemicals, such as histamine, into the bloodstream.
Chronic hives are welts that last for more than six weeks and return often over months or years. Chronic hives do not put you at sudden risk of a serious allergic reaction (anaphylaxis) . However, if you get hives as part of a severe allergic reaction, seek emergency care. Symptoms of anaphylaxis include dizziness, trouble breathing, and swelling of the tongue, lips, mouth, or throat.
Treatment for hives may include a combination of antihistamines, cold compresses, or anti-itch balms to ease the symptoms. Severe episodes of urticaria may require temporary treatment with prednisone, a similar corticosteroid medication, or an immune modulator, which can reduce the severity of the symptoms. If the cause cannot be identified, even after a detailed history and testing, the condition is called chronic idiopathic urticaria. Chronic hives may also be associated with thyroid disease, other hormonal problems, or, in very rare instances, cancer.
