When the body is hot, the skin itches mainly because of cholinergic urticaria. Cholinergic urticaria may be the patient’s allergy to heat or sweat, the body will release a large number of neuromediators, such as acetylcholine, when the body is hot. At this time, red spots and wind bumps of varying sizes appear on the skin, accompanied by intense itching. These lesions can usually subside within 24 hours and leave no trace after subsiding, but can be repeated. Patients can, on the one hand, use topical glycerite lotion to relieve itching, and also take oral antihistamines, such as loratadine, cetirizine, ebastine and other anti-allergy treatments. Therefore, patients should avoid high temperature stimulation. When the body is hot, itchy skin may also be other reasons, it is recommended that patients seek medical treatment by a professional doctor for standardized diagnosis and treatment.