Urticaria and 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.

Cutaneous allergy

Cutaneous allergy encompasses a broad spectrum of clinical presentations with complex underlying immunological mechanisms. Allergy may beĀ  considered to play a role in disorders that include atopic dermatitis, contact dermatitis, urticaria, angioedema, anaphylaxis and adverse drug reactions. The skin phenotypes associated with allergy are more commonly exhibited in non-allergic disease and so a high proportion of patients who consider themselves allergic in truth have other, nonallergic explanations for their presentation.