I've begun the two per day regimen and I must say that this Chantix is really quite remarkable, the "Urge" has become quite manageable; almost as though it's not really there. I'm down to no more than a handful (meaning 5 or 6 maximum) of smokes per day by simple "procrastination". If I feel a mild urge, I simply put it off for a while, saying to myself "maybe in an hour or two". This is also helping to break "routine", whereby one smokes at certain times, or as a punctuation, whether you need to or not. I'm sure everyone who smokes understands what I mean.
As for the side effects, well, nothing Earth shaking to report. Some nausea, but I get some nausea from other medications that I'm taking, so it may not be attributable to the Chantix. I'm now taking all the meds with food which is a good practice anyway. My sleep has been restless, but that has been the case for some time now. What has changed is I awaken frequently, feeling wide awake, but seem to go back to sleep rather quickly. I'm having some pretty bizarre dreams, but they're rather entertaining - I think. I can't say that I remember much about them, but then again, I haven't felt particularly terrified either.
That's about all I can say for now except that this program does take some effort on your part, but, from my limited experience, somewhat less than anticipated. Cigarettes are a two-pronged addiction; one physical dependence and one habitual. Chantix is quite amazing at the way it almost removes the physical withdrawal, but the habitual side is up to us.