Urticaria, also known as hives, is common, and affects about 20% of people (one in 5 people) at some point in their lives. Urticaria consists of pink or white raised areas of skin resembling nettle rash, known as wheals (also spelled weals), which are usually itchy. The wheals are often round or ring-shaped. Wheals can also appear as lines when the skin is firmly stroked. They can appear anywhere on the skin. Individual wheals typically disappear of their own accord within 24 hours without a trace, although the course of the condition is longer.
Angioedema is characterised by deeper swelling in the skin, which may take over 24 hours to clear. It is not usually itchy and can affect the lips and tongue. Some patients have one or the other condition, others have both.