Itchy red spots on the body are mostly caused by inflammatory skin diseases, such as allergic skin diseases, infectious diseases, prickly heat and so on. 1. Allergic skin diseases: If the skin has red spots and herpes, and accompanied by itching and other symptoms, most of them are caused by allergic skin diseases, such as contact dermatitis, acute urticaria and so on. 2. Infectious diseases: common rubella, measles, most of the viral infectious diseases, clinical symptoms manifested as red maculopapular rash, accompanied by varying degrees of itching. 3. Prickly heat: clinical symptoms of red macules, accompanied by itching and other symptoms, mostly in the hot environment for too long. Patients with red spots, accompanied by itching and other symptoms, it is recommended to choose a regular dermatology hospital for examination, according to the results of the examination to choose the correct treatment program.