Varenicline
"I was not expecting Champix to work as efficiently but I am surprised by how effective it is. I'm on my eighth week of taking Champix, and my fourth week of total quitting. I smoked as normal for the first two weeks, stopped smoking through the day, then got down to one or two smokes a day before quitting completely. It just seemed effortless.
The side effects have been interesting. My dreams have been very vivid but not disturbing. The nausea has been easy to manage by eating something like yogurt before taking, and constipation remedies are easy to find. I would recommend it to anyone, and indeed do."