Urticaria, also called hives, are red, itchy, swollen areas of the skin that can range in size and appear anywhere on the body.
Usually, in cases of new onset acute urticaria, the cause is readily identifiable. Often it is due to an allergy to drugs, food, or contact allergens like latex or pets. These hives usually go away spontaneously or by avoiding the allergic trigger. In some cases, medicine like antihistamines is needed to treat symptoms or prevent recurrence.
Some people have chronic urticaria that occurs almost daily for months or, in some cases, years. For these individuals, scratching, pressure or stress may aggravate hives. But in most cases, a trigger is not evident.