The liquor is treated as an ingested poison, although some of its effects are temporary (lasts 1d12 hours + 1 hour per shot). Any damage taken is considered half lethal and half nonlethal once the effects fade. Until that time, all the damage is considered lethal.
Anyone who drinks a shot of the blue liquor must make a Fortitude save (DC 12) for each shot-full. The first failure dulls the senses (-1 to Intelligence and Wisdom-based skill checks). The second failure leaves the character vulnerable (-1 to AC, -1 to attack rolls). The third failure hurts the body (1d3 points of poison damage). Each failure after that is at a -1 to the Fortitude save and doubles the damage (1d3, 1d6, 1d12, 2d12 etc).