You better not be underage any more if you're at your high school reunion, so there's no need to spike the punch. Just go to the bar and get a drink, or pull out your bottle or hip flask and have at it.
And what's with the *zzzip* ? Are you planning on pissing in the punch? I went to school with a guy who would have done that, but he got shot to death in an abortive robbery, so who the fuck are you?