This is my story and I an sticking to it!! I started taking Chantix on June 1, 2008, by June 9 I had quit smoking. YEA!!!!! I continued taking Chantix for about a month and then quit. In Aug my Dr put me on Welbutrin for mild, very mild, depression. In November, I gave in, what a dummy, and after a day or two, I started taking Chantix again, to quit. Well, after taking it for about 3 weeks, there was nothing, no effect on me at all. So, I am thinking that the Welbutrin is the culprit, but according to all of the EXPERTS, there is no interaction between the two. So now I don't know what to think. I am going to start on Chantix again today, and hope for the best. Has anyone had this problem the second time around, maybe I have built an immunity to Chantix and it will just take longer to work????? Any advice.