Urticaria is a common disease that progresses with attacks of erythema, swelling and pruritus that usually disappear within 24 hours. It may occur in any part of the body and new lesions may occur in other regions while urticaria in one region regresses. Angioedema is characterized by swelling, itching, burning and blister formation in the deeper regions of the skin. It is often observed on the eyelids, lips, palms and soles. Urticaria and angioedema can be seen separately or together. The main reason for both is histamine secretion from the mast cells that are responsible for allergy of the skin.
The most commonly blamed factors are infections, various drugs, food and additives, and emotional stress. However, physical factors (sun, cold, pressure), agents contacting the skin (causing contact urticaria), insect bites, and factors that cause increased body temperature or sweating can also lead to urticaria development.
There are various types of urticaria. The most common type is ordinary urticaria. It is roughly divided into two based on its duration. The condition is defined as acute urticaria if it lasts shorter than 6 weeks and as chronic urticaria if present for more than 6 weeks. Further analyses are required to exclude underlying systemic diseases in chronic urticaria.
The diagnosis of urticaria is easy and no allergy tests are required in many types. The agents most frequently used in the treatment are antihistamines. Treatments affecting the immune system such as systemic steroids, cyclosporine and omalizumab are preferred in resistant and severe cases.