Low-Dose Naltrexone Combined With Bupropion to Stop Smoking With Less Weight Gain

Inclusion Criteria: * Ages 18 and older * Willingness and ability to give written consent * Smoking at least 10 cigarettes per day for at least 1 year * Baseline expired carbon-monoxide level of at least 10 ppm * Weigh at least 100 lbs. * English-speaking * One person per household * At least 1 prior quit attempt * Concern about gaining weight. This will be assessed using a questionnaire that will provide a rating system to determine qualified participants. Exclusion Criteria: * Pregnant or nursing women or women attempting to conceive * Serious current neurologic, psychiatric or medical illness, including unstable cardiac, hepatic, or renal disease and diabetes and hypertension * Current alcohol dependence * Current use of opiates, and/or a urine toxicology screen positive for opiates * Chronic pain conditions necessitating opioid treatment (naltrexone, an opioid antagonist will make these medications ineffective) * Evidence of significant hepatocellular injury as evidenced by AST or ALT \>3 x normal or elevated bilirubin * History of cirrhosis * Body mass index (BMI) greater than 35 * History of anorexia nervosa or bulimia * Current major depression * Currently taking Toprol-XL (or metoprolol succinate) * History of seizure disorder or serious brain injury * Current use of smokeless tobacco, pipes, cigars, nicotine gum, nicotine patch, nicotine inhaler, nicotine lozenge, nicotine nasal spray, or bupropion * Previous hypersensitivity to bupropion * Patients requiring concomitant therapy with any psychotropic drug * Participation in the Framing Messages for Smoking Cessation With Bupropion study (HIC#: 10880)