Angioedema is an allergic condition similar to hives. While hives develop on the skin's surface, angioedema is a swelling of the deeper layers of the skin. It most often occurs on the hands, feet and face (lips and eyes). Hives and angioedema may appear together or separately on the body. Angioedema usually lasts one or two days and may recur with or without hives over an indefinite period of time.
If the angioedema occurs in the throat, normal breathing or swallowing can be blocked and emergency measures must be taken. This is a rare occurrence, and is associated with acute allergic reactions and not with chronic urticaria or angioedema.
Hereditary angioedema is an inherited disease that differs from other types of chronic angioedema. Serious swelling can occur in the airways such as the larynx, tongue and throat, as well as on the face and other extremities. It has been demonstrated that a blood protein deficiency is the cause of this inherited illness.