M.B.
Responding to previous post re: "double dose"- it is considered "piggybacking" Motrin and Tylenol, and it should be Tylenol every 4 hours and Motrin every six, not taken together! Double check with your pedi, but I am pretty sure that is how you do it!
The pain is what is causing him to want to suck, have you tried a paci? Also, I agree with the frozen washcloth, and if he is old enough, maybe a popsicle to help keep the area cold. Once the tooth cuts the gum, he will OK. Hopefully that will be sooner than later! :)