You shoulda drank some water, prevents a hangover better than anything else. Because you know a hangovers just dehydration, taking a pain reliever would help, but what you would need is some liquids. I myself try to drink a bottle of water for every 2 hours of drinking, and I have never had a hangover.
That helps if you have the forethought to do it before going to bed after drinking. If you did not however, a shot of whatever you were drinking helps for the morning after. Hair of the dog that bit you. And Winston, you should come down here.
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