I am on bf and formula for my LO. He is just 2 months and I recently encounter toothache and I had painkillers(arcoxia) from dental but the medicine is strong don't know if I can still bf my LO after I take the medicine?

I'm not a doctor, however after googling, most websites suggest you to stop breastfeeding temporarily while taking this painkiller as it is very strong. You can pump and dump your breastmilk temporarily and restart again once you stop the painkillers.

Agree with the mom above, pump and throw. If really necessary, consult your dentist and see if he can prescribe any other alternatives which may not disrupt the bf.