I have been using this quitting smoking method for 3 weeks or so and I'm smoking less. Hopefully will have quit by Thanksgiving. Also impt. to note that I rec'd 2 of the same filters in the package, each filter should be numbered 1-4. I got two number 3's and no number 4. One phone call and less than one week later I rec'd the right filter from the company, no questions asked. Also originally, I remember reading a review about how the nicotine got into the reviewers mouth and for that they gave it one star. Funny thing is, that person obviously never read the directions. The filters must be cleaned regularly. And yes, cleaning the filter is part of what helps you to quit because it is disgusting!! I've got three friends doing this with me now. I recommend trying this method of quitting.