Water. Water. Water. In addition, you could have sparkling water, club soda, and mineral water—that’s what I order when I’m out socializing with friends. And I always ask for extra lemon or lime. As long as you don’t eat the lemon or lime, that’s fine. I’ve grown to love it!
You can also have pretty much any variety of herbal tea, as long as it doesn’t have any sweetener in it.
Black tea and black coffee are also fine, but watch the caffeine. It will flood the nucleus accumbens with dopamine, and will therefore impede the healing you want to be happening there. One cup in the morning is fine. A whole lot more, though, and you may be messing with your recovery.