Will it cause discomfort?

During a root canal the tooth is numb from the use of xylocaine. There should be no feeling at all. If you’re numb you’re numb and if you’re not you’re not! But the dilemma which arises is what to tell a patient to expect afterward. In 95% of the cases afterwards there is only minor swelling and tenderness, but in 5% of the cases it can be extremely uncomfortable. That’s why we always prescribe very strong pain medication with every root canal. You should not drive or drink alcohol with it. My advice is to take some Advil, Tylonol, or aspirin (whichever suits you) while your tooth is still numb to ease the transition when the anesthetic wears off. Then if there is any discomfort you will have a prescription for a very strong pain medication that you can fill if you need to.