Gabapentin for Smoking Cessation
Condition: Cigarette Smoking; Tobacco Use
Intervention: Placebo; Gabapentin - 1800 mg/day; Gabapentin - 2700 mg/day
Intervention description: Placebo pill - non active sugar pill designed to look alike to the gabapentin medication; gabapentin - 1800 mg/day for 12 weeks.; gabapentin - 2700 mg/day for 12 weeks.
Intervention MeSH terms: Gabapentin
Phase: Phase 2
Study type: Interventional
Primary purpose: Treatment
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Care Provider)
Enrollment: 80.0
Sex: All
Minimum age: 18 Years
Maximum age: 65 Years
Healthy volunteers: Accepts Healthy Volunteers
Keywords: tobacco; smoking; gabapentin; abstinence

Summary:

      Gabapentin is an anti-epileptic agent that has shown preliminary evidence of efficacy for
      improving symptoms of cocaine and alcohol withdrawal in pilot studies. Since the neurobiology
      of alcohol, cocaine and nicotine withdrawal is similar, the preliminary evidence of efficacy
      of gabapentin for symptoms of alcohol and cocaine withdrawal suggests, that gabapentin might
      likely help nicotine withdrawal symptoms and thus tobacco abstinence. The effect of
      gabapentin on two of the neurotransmitters, gamma-aminobutyric acid (GABA) and glutamate
      further suggest a potential therapeutic mechanism for gabapentin in tobacco abstinence.
      However, the exact mechanism of action of gabapentin is currently not known. We have recently
      completed an open label pilot trial of gabapentin for tobacco abstinence involving 50
      smokers. The findings from that study provide promising preliminary results and suggest that
      further testing of gabapentin for helping cigarette smokers quit tobacco use is worth
      pursuing. Overall, gabapentin is well tolerated and has low abuse potential.

      Our goal is to evaluate novel, safe, acceptable, and effective therapies that may help
      increase tobacco abstinence rates. Currently, no randomized trials testing the efficacy of
      gabapentin for smoking abstinence have been published. While our previous study provides
      promising evidence regarding the potential efficacy of gabapentin for smoking abstinence, an
      additional dose ranging study is needed prior to pursuing a large randomized trial. The
      primary aim of the dose ranging study will be to obtain additional evidence of efficacy, and
      information on the optimal dose of gabapentin to employ in the larger randomized controlled
      trial.
    

Eligibility criteria:

        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.