Firstly most of the smokers I know are Drinkers, the two go together.
When you take Champix be very careful how much booze you consume, it is very easy to start to get high regularly.
With me Champix changed the taste of Coffee, so rather than replace it with water etc I drank less so in the evening I drank more! After 4 or 5 weeks on it and the weather got warmer I started drinking very heavily (easy to do when you stop smoking).
I have had some bad after effects of champix but as it is a new drug I would suggest this, After 8 weeks ask for the half strength tablets taken twice a day, then for the last two weeks 1 a day.
I stopped suddenly after 9/10 weeks and it caused me all sorts of problems from withdrawing abruptly. Take it steady... there is no rush. For me personally it started to accelerate my drinking so I had to stop it.
Good luck to you all.