Clinical Definition

Angioedema is a non-pitting edema that affects the dermis and subcutaneous layers, most often involving the tongue, lips, face and throat, but also less commonly the genitalia and viscera. Edema can also affect the airway, a potentially life-threatening event. If angioedema is severe, emergency treatment to ensure an open, functioning airway is needed.

In Our Own Words

Allergies, hives and certain kinds of angioedema are linked in that they involve reactions to histamine. But unlike hives, angioedema is a deeper swelling that occurs below the surface of the skin, usually around the lips and eyes but sometimes affecting other areas or the body. An allergic reaction to either food or medicine or an allergic reaction to an insect sting is the typical trigger.

Hereditary angioedema is a rare genetic condition involving recurrent angioedema that is not associated with itching or hives.

Sometimes the cause of angioedema is unknown.

In all cases, if angioedema affects the tongue, throat or airways, emergency treatment is crucial to ensure the airway is open and breathing is not compromised.