It is relatively normal for a child to have a fever after a shot. Most fevers are due to bacterial or viral invasion, causing symptoms of upper respiratory tract infection. The course of the disease is cyclical, and without the use of glucocorticoids or antipyretic and analgesic drugs, there is usually no immediate reduction of fever. If the body temperature exceeds 38.5°C, oral ibuprofen suspension drops can be given for infants and children to reduce fever. In case of persistent high fever, the medication can be repeated once in 4-6 hours, no more than 4 times a day. It can be combined with traditional Chinese medicine, such as Antelope Horn Punch and Pediatric Niuhuang Qingxin San, which can both reduce fever and prevent high fever from causing convulsions and seizures. If the body temperature does not exceed 38.5℃, you can take pediatric aminophenalkylamine granules orally, which can treat and relieve the symptoms of fever caused by cold. It can be combined with Chinese medicines such as Blue Scutellaria Oral Liquid and Pudilan Anti-inflammatory Oral Liquid to clear heat and detoxify the toxins.