Sore throat with phlegm during breastfeeding may be an upper respiratory tract infection, which requires timely medical examination to identify the cause and treatment under the guidance of the doctor. If the infection is caused by bacteria, you can use antibiotics under the guidance of the doctor, such as penicillin, cephalosporin, etc., these drugs have no effect on breastfeeding. If it is a viral infection, it can be treated with oseltamivir under doctor’s supervision. If you have an upper respiratory tract infection such as a sore throat with phlegm during breastfeeding, you need to wear a good mask and do a good job of personal protection so as not to infect your child. If you have a high fever, you should stop breastfeeding, empty your milk and wait for your temperature to normalize before breastfeeding again. Breastfeeding women should also drink plenty of warm water to increase the body’s metabolism. If you have a sore throat with phlegm during breastfeeding, you should seek medical attention and use medications that do not affect your child under the guidance of your doctor, rather than taking medications on your own.