Chantix
"Excellent at helping to quit smoking, as long as you are: a) seriously ready to quit; and b) prepared for the pattern changes (i.e. smoking in the car, smoking while on the phone, after meals, etc.)  Worked really well for the first 3 to 4 weeks, but then dropped me into a severe depression and a downward spiral in the 4th and 5th weeks.  I tapered back and eventually stopped taking it altogether starting in week 6 or so.  At week 10 I ended up in the back of a police car on my way to the ER after a serious suicidal episode.  PLEASE BE CAREFUL WITH THIS DRUG!  I've suffered from depression (never diagnosed or treated, but we know ourselves, don't we?) my entire life on and off, but this was bad.  I'd go cold turkey, all things considered..."