Not great. Frankly, the best results on a stop smoking drug is nicotine replacement which about doubles your likelihood of quitting. Zyban increases your likelihood of quitting in their studies from 20% that day to 25% (these are not very good numbers). I have better results with a multistep approach. First, having a gun to your head is important for motivation. Heart attack, stroke, hospitalization from lung problems are clues.... and one 30 yr old quit when I showed that 1) the 7 months of erectile problems were the same 7 months he went back to cigarrettes and 2) it took 2 seconds for blood to get to the tips of his fingers after I pressed on them.... similar circulation would occur in all extremities........... Second, nicotine replacement. Cannot say which is best for you. Personally, I do not object to E-cigarettes, and similar things were FDA approved in the past... but currently a bit controversial, and patches, and gum not controversial. Third.... addiction is a place you move from, not thinking better thoughts. Changes in the external millieu are helpful. So.... 1) set a quit date and tell everyone about it. Personally, I had my religious group pray for me on that date. 2) get cigarettes, lighters, ashtrays out of the house on that day. 3) and this is my own invention (har, har, no, but I m not telling where it s really from!) get post-its or colored duct tape or sticky gold stars. Whenever you have a trigger to smoke AND YOU DON T put a star on where the trigger occurred. Soon you will be surrounded by triggers of positives rather than negatives! Good Luck !