Niacin works, but not as an entire course-of-action, but as a supplementary to the work you are already doing. You should also try to stay clean for an extended-period prior to drug testing. I was actually going to write a detoxification guide, but I never quite got around to it, or really found enough time. But here is a good website with a lot of information about Niacin and its role in bodily detoxification.

The role of niacin in detoxification
ThePeacockNamethTom Reviewed by ThePeacockNamethTom on . NIcotinic ACid vitamIN B3(Niacin) I heard that Niacin helps clean your system out fast if u take enough.. anyone have experience with this at all? I have 50 250mg Niacin pills and my test might be on Thursday I smoked a few times over the weekend. I also have cranberry juice for purifying my system. Rating: 5