well if your a heavy smoker, like once a day, it will come out completely after about a month, but if your a light smoker most the time in comes out in about 1 week or less. I had a friend that did it one day, then 4 days later her dad took her for a piss test and she passed, so nothing to worry about really...it will deffinantly come out by then...but if i were you i still go safe and try to drink alot...peace