The Effect of Varenicline (Chantix) and Bupropion (Zyban) on Smoking Lapse Behavior

Inclusion Criteria:

- ages 18-55

- able to read and write in English

- Smokers

Exclusion Criteria:

- any significant current medical or psychiatric conditions that would contraindicate
smoking

- current Diagnostic and Statistical Manual IV abuse or dependence of other substances,
other than nicotine dependence or alcohol abuse

- positive test result at intake appointments on urine drug screens conducted for
opiates, cocaine, or benzodiazepines

- women who are pregnant or nursing

- suicidal, homicidal, or evidence of current severe mental illness

- participants prescribed any psychotropic drug in the 30 days prior to study enrollment

- blood donation within the past 6 weeks

- individuals seeking treatment for smoking cessation or have attempted to quit smoking
within the past 3 months

- specific exclusions for bupropion administration not already specified, including:
have taken monoamine inhibitors in the past 6 weeks; history of anorexia or bulimia;
previous hypersensitivity to bupropion; history of alcohol or drug dependence in the
past year; history of seizure disorder of any etiology

- known allergy to varenicline or taking H2blockers

- participation within the past 8 weeks in other studies that involve additive blood
sampling and/or interventional measures that would be considered excessive in
combination with the current study