I've talked to literally hundereds if not thousands of people taking or who have taken chantix. It is NOT the last resort, actually it's what we recommend if the person has no preference or has not had success w/ a different method in the past.
Most common side effect by far is an upset stomach (take it w/ food for sure).
Vivid dreams is second.
I've talked to 2 or 3 people w/ mood changes.
The FDA is looking in to reports of suicidal thoughts/erratic/agressive behavior- it has NOT been proven that chantix had anything to do with it. When the FDA originally was running their studies on it before approving it, there was not a significant increase vs. placebo when it came to mood changes/depression etc.
Some people experience these "side effects" simply from quitting smoking in general, especially if they have some underlying or diagnosed psychological condition to begin with. That being said, if you have been diagnosed w/ any psychological condition (bipolar/depression/ etc) then it is a good idea to be careful when taking chantix and let your doctor know if you experience any mood changes.
Also, I make it a point to ask everyone who has discontinued the medication after 12 or 24 weeks if they felt any different, and have not had anyone say they felt anything at all.
That being said, everyone is different, there is always that small chance that you will not react well with the medication.
It really is a shame how public these "side effects" have become in the last few months...Before then, everyone was excited to use it- it was exciting for me as well because it DID work so well for *most* people who used it. At the time, I had not spoken with a single person who had any SE's other than gastrointestinal issues or dreams.
I wouldnt be scared in trying it out- you start at a low dose for the first few days, so if you are going to experience any side effects, you'll probably experience a mild version of them on the lower dose.