Percocet is narcotic. Whatever medications you take are transfered to the baby through the breastmilk. Talk to your doctor about available options regarding pain medication.
Under absolutely no circumstances should you breastfeed with taking percocet. Your breast is like a faucet to your babies mouth. What comes out of you goes in your baby.
As an R. N. I have difficulty in not writing "nursespeak" but I'll try so I won't be accused of cheating. Percocet is a narcotic. The drug you take passes through to your breast milk The baby is at risk of becoming unconscious or die from the effect of this narcotic.
It is generally recommended that breastfeeding mothers not take narcotics while breastfeeding. The effects vary depending on studies but it is not considered healthy.