Eligibility Criteria

Inclusion Criteria:

- Female and male smokers, aged 18 to 50 years;

- History of smoking daily for the past 12 months, 10-25 cigarettes daily;

- Not seeking treatment at the time of the study for nicotine dependence;

- Have a FTND score of at least 5 and CO level > 10ppm;

- In good health as verified by medical history, screening examination, and screening
laboratory tests;

- For women, not pregnant as determined by pregnancy screening, nor breast feeding, and
using acceptable birth control methods.

Exclusion Criteria:

- History of major medical illnesses that the physician investigator deems as
contraindicated for the patient to be in the study;

- Regular use of psychotropic medication (antidepressants, antipsychotics, or
anxiolytics) and recent psychiatric diagnosis and treatment for Axis I disorders
including major depression, bipolar affective disorder, schizophrenia or panic
disorder;

- Abuse of alcohol or any other recreational or prescription drugs.