Gabapentin for Smoking Cessation

Inclusion Criteria: 1. Are between 18 to 65 years of age 2. Have smoked ≥10 cigarettes/day for the past 1 year or more 3. Are willing to make a quit attempt 4. Are able to participate fully in all aspects of the study; and 5. Have been provided with, understand, and have signed the informed consent. Exclusion Criteria: 1. Meet diagnostic criteria for current major depressive disorder or lifetime history of bipolar disorder or schizophrenia. Patients with mild or moderate depressive symptoms as assessed by the CES-D and determined by the physician, but who do not meet current diagnostic criteria for major depressive disorder, will be included 2. Are currently (within past 30 days) using antipsychotics, or antidepressants 3. Are currently (in previous 30 days) using any tobacco treatment program (i.e., behavioral therapy, nicotine replacement therapy, bupropion SR, clonidine, or nortriptyline) 4. Have used an investigational drug within the 30 days prior to enrolling in this study 5. Have recent history (in the past year) of alcohol abuse or dependence as assessed by the CAGE questionnaire and study investigators 6. Have a recent history of drug abuse as assessed by the Drug Abuse Screening Test 20 (DAST-20) and physician interview 7. Are pregnant, lactating, or of child bearing potential, likely to become pregnant during the medication phase and not willing to use contraception. The following birth control measures are acceptable: birth control pills, approved intra-uterine contraceptive devices, the use of two combined barrier methods (diaphragm with spermicide or condom with spermicide), injections, surgical sterilization and abstinence 8. Have a history of any major cardio-vascular events in the past 6 months including unstable angina, acute MI or coronary angioplasty 9. Have clinically significant acute or chronic progressive or unstable neurologic (myasthenia gravis), hepatic, renal, cardiovascular, respiratory (bronchospastic disease) or metabolic disease 10. Are currently on the following prescribed medications known to interact with gabapentin and unable to stop them during the study: Maalox®, cimetidine and morphine. Patients will be cautioned not to use sedatives (such as benzodiazepines, antihistamines, anti-cholinergics, trazodone, zaleplon, anti-psychotics, barbiturates, opiates, zolpidem and eszopiclone) during the study 11. Have another house-hold member or relative participating in the study 12. Have known allergy to gabapentin or its constituents; and 13. Are professional drivers or operators of heavy machinery and unable to refrain from these activities during the medication phase of the study.