My Dad used Lidocaine prior to surgery to relieve the sore spots in his mouth so he could eat and speak. He simply swabbed it on the affected areas. It provided only about 20 minutes of relief for him, which was long enough for him to get the food down, but his pain was pretty severe. It was a blessing for him. It comes in different stregnths and he was using the low dose at the maximum times per day. You do have to be careful about how much you use, so it's probably not a good substitute for a narcotic pain reliever, but it sure does provide some relief for the break thru pain.