As early on as you can, craft an antidote. There will be a chance that monsters will throw up all over you and cause you to be poisoned. The poison will cause you to lose 1 health point per turn, so it's always good to have one of these on hand. However, there's a chance that the monsters will never throw up on you. So this will be "luck" based. You will receive the achievement when you use an antidote while you are poisoned.