The common clinical adverse reactions of MMR vaccine include skin reaction, fever, allergy, etc. 1. Skin reaction: within 24 hours after MMR vaccination, redness, swelling and pain may appear at the injection site. 2. Fever: Some people may develop fever after MMR vaccination. If the temperature of low fever does not exceed 38.5℃, physical cooling can be considered by scrubbing the body with a wet towel. If the temperature exceeds 38.5℃, you may need to cooperate with your doctor to use antipyretic drugs such as ibuprofen and acetaminophen. 3. Allergy: A very small number of patients may develop allergy after vaccination, which is mainly manifested by skin rashes. If the allergy is more serious, it may lead to purpura, laryngeal edema, which is a serious threat to life and health. There may be other clinical reactions to MMR vaccination, and immediate medical attention is recommended in case of severe discomfort. Medications should be used under the guidance of a medical professional, and should not be used arbitrarily on their own.