angioedema

Urticaria, also known as hives, and angioedema, where the swelling occurs below the skin instead of on the skin, are extremely common but there is a misconception that the most likely cause is an allergic reaction. Chronic urticaria in particular is rarely due to allergy. Equally for angioedema, many will consider the exceptionally rare hereditary angioedema (HAE), but in fact other medical causes are the most likely, in particular the use of angiotensin-converting enzyme inhibitor (ACE-I) drugs.