Red on the baby’s body, according to different situations to take different treatment methods, the following are common: First, newborn erythema. Most of them appear within a week after birth, mainly erythema on the trunk, not accompanied by itching, most of them fade within 1-2 days, without other uncomfortable symptoms. Second, allergic dermatitis. Block erythema appears after consuming certain drugs or food, mostly accompanied by itching, will gradually reduce after stopping the above drugs or food, if necessary, oral cetirizine, vitamin C and other anti-allergic treatment can be given. Third, viral dermatitis. Most of them are accompanied by fever and loss of appetite, etc. If necessary, oral antiviral treatment such as acyclovir can be given. Fourth, other specific diseases, such as immune system diseases, 1-2 weeks before the appearance of erythema, most of them have a history of acute upper respiratory tract infection, in addition to skin erythema, will be accompanied by mental depression, generalized muscle weakness, etc., need to promptly go to the hospital for examination.