The overall goal of this research is to increase our understanding of the role of individual
genetic differences in response to bupropion treatment and the psychobiological mechanisms by
which genetic and treatment factors interact in the smoking cessation process. The ultimate
objective is to provide information necessary to match bupropion vs. behavioral counseling
cessation treatment to those smokers with the greatest need and likelihood of benefit. This
study is a double-blind randomized placebo-controlled clinical trial of bupropion HCL (brand
name Zyban) in adult male and female smokers. The factorial design includes one treatment
factor (bupropion 300 mg/day + counseling vs. placebo + counseling) and several subject
factors (e.g. genotype, personality). Smoking history, psychological status will be assessed
at baseline and blood will be drawn for genotyping. Bupropion or placebo will be delivered
over a 10-week treatment period and subjects will be instructed to quit smoking after two
weeks of medication (week 3 of treatment). All subjects will also receive a 7-week group
behavioral smoking cessation treatment (over an 11 week period). This study may yield
information that will help clinicians identify the most effective smoking cessation treatment
for a particular patient, based on his/her background.