Breastfeeding should not be done until 48 hours after the painkilling injection, depending on the body’s metabolism. The painkillers injected during surgery are anesthetics, which are relatively long-lasting and take about 48 hours to be completely metabolized by the body, so if you breastfeed during this period, there may be residual anesthetics in the milk. Therefore, it is recommended not to breastfeed for 48 hours after the injection of anesthesia, and the exact time varies from person to person. Due to individual differences and different metabolism of each person, the time for breastfeeding after anesthesia injection may vary to some extent, but try to control it after 48 hours. It is advisable to consult your doctor further.