Generally speaking it wont be a problem if you pop a tylenol before going to bed after drinking. It strains the same degradation pathways as ethanol does though and as both have toxic metabolites that better get degraded further asap that's probably not a good idea. As long as your liver is not already damagd you should be fine but why risk it for the doubtful possibility that it might prevent a headache. As far as I'm concearned lots of water and a multivitamin pill are mostly what I use.