Cholinergic urticaria is the most common cause of itching when the body is exposed to heat. Cholinergic urticaria cannot be ruled out as the cause of the itching sensation after exposure to heat. Because this disease occurs more often in young people, especially after exercise, emotional stress and drinking alcohol will lead to a rapid rise in body temperature. In response to both internal and external stimuli, round, pimple-like bumps appear within minutes, accompanied by a sharp itching and burning sensation. Cholinergic urticaria, once exposed to heat, causes cholinergic nerve impulses to release acetylcholine, which, when stimulated to mast cells below the skin, releases a number of pruritic inflammatory stimulants that induce a tingling sensation in the body. However, such problems usually do not cause significant skin damage and do not require special treatment, and the symptoms will resolve on their own in about half an hour to an hour or so. Occasionally accompanied by systemic symptoms caused by acetylcholine (such as salivation, headache, slow pulse, pupil narrowing and spasmodic abdominal pain, diarrhea), etc. Dizziness can be severe enough to cause fainting. When the patient’s body is exposed to heat after the occurrence of tingling all over the body, you can first observe for 1~2 hours. If the symptoms are not relieved or disappear, this should go to the local hospital in time for relevant examinations, early detection of problems early treatment.