Adverse reactions such as fever, diarrhea, vomiting, loss of appetite, and drowsiness are common and may occur after children are injected with the quadruple vaccine. If allergic reactions such as respiratory distress, urticaria, anaphylaxis, etc. occur after the injection, timely hospital treatment is required. Quadruple vaccine is used to prevent infections caused by diphtheria, tetanus, pertussis and Haemophilus influenzae type b. Adverse reactions such as tenderness at the injection site, erythema and hard nodules, fever, vomiting, diarrhea, loss of appetite, drowsiness, irritability, abnormal crying, and sleep disorders may commonly occur after injection. If any adverse reactions not already listed in the instructions occur, consult your doctor promptly. If other severe allergic reactions such as respiratory distress, urticaria, anaphylaxis, etc. occur in children after vaccination, they need to go to the hospital in time for medical treatment.