Believe me, I tried to avoid it. But up against the wall, with the guy's hand around my throat and no bottles or weapons within grabbing distance, there were only two options: Kick him in the balls, and spit liquor in his eyes. I tried the first one and he didn't even flinch, so I pretty much had to.
Made him pay for it afterward, though. Pretty sure he didn't expect me to hit him with a chair.