Urticaria is a common skin, mucous membrane and vascular reactive disease, which is manifested as an intermittent itchy wind mass. The center of the skin lesion can subside, and the appearance is circular or multi circular. Clinically, it is manifested as localized, protuberant, easily subsided edematous erythema, often accompanied by itching. The common symptom is acute urticaria, which means that patients with a course of less than 6 weeks have a sudden onset. First, the skin itches, and then the wheal quickly appears. The wheal lasts for a few minutes or hours, then disappears without leaving traces. A single damage rarely lasts more than 12 hours, but new wheals can continue to appear, several times a day, and the whole body is suffused with itching or burning.
