My pediatrician suggested against giving him Tylenol before hand. You really want to see how he handles it first then give him meds. Also check his temperatures regularly because they can cause fever and they do cause baby to be more sleepy for a few days. The area where they put the shots may get a bit swollen just ice it down a bit.
My pedi recommended tylenol before shots. The shots made my son sleepy but I did give him the tylenol beforehand also. Had no problems at all its just upsetting for us mamas. lol
Please give your lo about ¾ of a teaspoon of infants Tylenol for the fever just before the appointment! Then about every 4 to 6 hours after that as needed!