Commonly known as hives, thigh wind patches are often accompanied by intensely itchy red patches. The onset may be related to an allergic reaction to medications, foods, insect stings or infections. However, there are also many patients who have no obvious triggers. 1. The typical urticaria lesion is an intensely itchy erythema. In patients with new-onset urticaria it may be related to allergies caused by drugs, food, insect stings or infections, but in many cases there is no specific cause, especially if the condition persists for weeks or months. 2. When sensitizing factors enter the body, they can cause the activation of a variety of inflammatory cells with mast cells at the core, releasing chemical mediators with inflammatory activity, including histamine, 5-hydroxytryptamine, etc., which can cause redness and swelling of the skin and a series of symptoms such as itching. Once the skin is swollen and itchy, it is recommended that the patient should consult the hospital in a timely manner and receive standardized treatment under the guidance of the doctor.