Angioedema is swelling of the blood vessels below the skin, which may be painful and accompanied by redness. It often appears on the face, tongue, hands or genitals. Angioedema may be caused by allergic reactions or may be caused by an infection or autoimmune disorder. One form of angioedema, called hereditary angioedema, runs in families.
Angioedema often appears at the same time as hives during an allergic reaction.