Hives are characterized as itchy red, raised welts (also known as wheals) on the skin’s surface that can spread or join together and form larger areas of raised lesions. They are generally triggered by exposure to an allergen. They tend to appear suddenly and often disappear equally as suddenly. Classically, individual hives last no more than 24 hours.
Hives are usually an allergic reaction to food, medicine or animals. They can be triggered to sun exposure, pressure, cold or hot exposure, stress, excessive perspiration or other, more serious diseases, such as lupus. Anyone can get hives. Hives may itch, burn or sting. They may need medical attention if they do not disappear on their own or reoccur frequently.
Hives lasting more than six weeks are known as chronic urticaria or, if there is swelling below the surface of the skin, angioedema. There are no known causes of angioedema, but it can affect internal organs and therefore requires medical attention. Long term treatment may require combinations of antihistamine and immunosuppression.
