Urticaria is a disease characterized by itchy weals, angioedema or both. It may be spontaneous or inducible, depending upon its pattern, and acute or chronic, depending on its duration. All types of urticaria are due to the release of histamine and other mediators from mast cell degranulation. The cause of the degranulation is often unknown but may be allergic (acute or contact urticaria only), autoimmune, infection or drug related; many cases remain unexplained (idiopathic) after investigation. Urticaria can be mild or severe. At the severe end of the spectrum, it can be a disabling disease with high levels of life quality impairment. Non‐sedating H1 antihistamines are the first line treatment for all patients. Non‐responders may benefit from the addition of second line (targeted) treatments, third line (immunosuppressives) treatments or a biological drug, of which omalizumab (anti‐IgE) is the best known and is now licensed for chronic spontaneous urticaria.
Keywords weals, angioedema, spontaneous, inducible, autoimmune, idiopathic, histamine, mast cells