Running causes itchy skin, consider cholinergic urticaria, or exercise-induced urticaria, both belong to a type of induced urticaria. 1. Cholinergic urticaria: mostly seen in young patients, mainly in the body exercise heat, emotional excitement, or after eating hot drinks, due to the body’s internal temperature rises, thus prompting the cholinergic nerve impulses, which act on the mast cells, resulting in skin tingling, itching and other symptoms. Generally within 30~60 minutes, it will subside on its own. 2. Exercise-induced urticaria: Most of them eat a few minutes after exercise or overeat within 4 hours, which will cause itchy skin, angioedema and itchy skin, which may be accompanied by other allergic symptoms, even shock, and is related to certain specific foods (such as wheat, etc.). It is recommended to go to the hospital for examination first, to clarify the cause of the disease and follow the doctor’s instructions for treatment.