Stinging and itching on the body when it is hot may be caused by cholinergic urticaria, eczema, and vegetative solar dermatitis. 1. Cholinergic urticaria: cholinergic urticaria may be caused by exercise or alcohol consumption and other causes of increased skin temperature, the patient will appear skin tingling, clammy, itchy, burning sensation and other manifestations. As a result, the patient will show that the body stings and itches when it is hot. 2. Eczema: the etiology of eczema is not clear, considering the environmental temperature and humidity changes, sun exposure, contact with allergens, heredity, immune function abnormalities and other reasons. Patients will appear itchy skin, papules, blisters and other manifestations. If the patient is in an overheated environment may induce eczema, the patient will appear a hot body itching symptoms. 3. Plant solar dermatitis: plant solar dermatitis is due to ingestion or contact with photosensitive plants, skin exposure to sunlight may appear itching, stinging, burning, blisters, respiratory difficulties and other symptoms, so the patient will have a hot body itchy performance. It is recommended that patients need to consult a doctor in a timely manner, who will choose appropriate measures for treatment after clarifying the cause of the disease.