Hi. I will be taking a cotinine test for my bariatric surgery. Surgery is not scheduled yet. I m suppose to be smoke free for 90 days. I ve been smoking a few here and there, but yesterday I bought a pk and have 3 left. After those are gone I won t be smoking anymore. I also smoke menthol. If I take niacin now and let s say my test is in 2 weeks, will cotinine still be detected? I ve seen niacin has benefits but I only want to take 500mg a day. And if I stop taking the niacin in lets say a week, could I pass the test in 2 weeks. And cotinine be out of my system for good?