What is angioedema?
Angioedema is an allergic reaction similar to hives, but it causes swelling deeper in the layers of the skin. It commonly affects the hands, feet, genitals and face (lips and eyes). It generally lasts longer than hives (which can occur simultaneously) but the swelling usually goes away in 24 hours. In rare cases, angioedema may involve the throat and tongue, blocking the airway and causing breathing difficulty. This can become a life-threatening emergency.