Just to confirm, THIS STUFF WORKS. I quit smoking two weeks beforehand, I actively work out as well, maybe 2 times a week. I drank this stuff the day of my test, maybe 3-4 hours before the test. I threw this up, but I drank the rest and filled it up two times. I was a heavy smoker literally, and my results came back negative which was shocking to me. I weight 140, in 5'7. I also eat pretty healthy but not perfect but I stopped eating out and sugar turning those two weeks as well. Good Luck