i've only smoked and drank at the same time enough to feel both once. we started out drinking vodka, smoked a joint (which was split between 5 people by the way), drank some more, and smoked another joint (at 4:20 in the morning haha). i didn't feel sick or anything, but obviously 2 joints between 5 people means i wasn't that high. so i'd say don't get blown out of your mind and then drink until the room starts spinning, just do enough of both that you get a nice buzz.