EWWWW...no!
Hair of the dog: A little more of "the dog that bit you the night before"!
Not to get too clinical, but a hangover, I'm told, is caused by alcohol that doesn't get fully metabolized because there was just too damn much for your liver to handle. The partially metabolized chemical left over is what's killing you...so if you add just a little more of the same, it converts back to the less painfull alcohol and the hangover stops...like BAM, almost right away. Since there's now not as much to handle, your liver can do it's job.
Disclaimer: This is from lessons I've learned from other people. I can not quote specific medical articles. Also, I am NOT a Doctor, although I did once play one is a school play...HA!