Wellbutrin is the generic drug for the trade name Zyban. They are not addictive. It is a mild anti-depressant and often prescribed for that, but they are also the "quit smoking pill". Your doctor will help you determine how long to stay on it. Generally, though, it isn't for more than six months. Long enough, in any case, that you are used to being a nonsmoker psycologically. You will be long done with the physical aspects of the addiction before the mental parts are overcome (which is what the drug is helping).
This is not a herion to methadone type thing, blazerrazor.