Chronic urticaria is caused by certain cells releasing chemicals known as histamines and other chemicals into the bloodstream, explains Mayo Clinic. Triggers for chronic urticaria can include sunlight, food, food additives, stress and infection. Other triggers include scratching, heat, cold, parasites or exercise.
Chronic urticaria is also known as chronic hives, states Mayo Clinic. It is not always possible to discover the cause of urticaria, nor is it always possible to discover why urticaria becomes chronic. Hives are red or white raised portions of the skin. Urticaria is chronic when it lasts for more than six weeks or recurs over months or years. The welts produced by urticaria can change in shape and size and appear and disappear rapidly.
Urticaria is twice as likely to occur in women than men and is most common in young adults, according to Mayo Clinic. Urticaria can produce severe itching, pain or burning, particularly when it causes swelling in the face, genitals, hands or feet. When the cause of chronic urticaria can be determined, the primary treatment is for the underlying condition. At the same time, or if the cause cannot be determined, treatment options include antihistamine medications, histamine blockers or anti-inflammatory medications. People with chronic urticaria may be able to minimize symptoms by wearing loose-fitting clothing and avoiding irritants.