St. John's Wort for Tobacco Cessation

Study Summary

After a steady decline for the last 50 years, the prevalence of tobacco use in the United States has reached a plateau of approximately 23%. Currently available treatments among adults are expensive and not efficacious for all tobacco users. New pharmacologic agents need to be developed and tested to achieve the Healthy People 2010 goal of less than a 12% adult tobacco use prevalence. Bupropion, an FDA approved agent for tobacco cessation, acts by inhibiting central synaptosomal reuptake of dopamine and norepinephrine. A widely used herbal antidepressant, St. John's Wort (SJW), shares a similar mechanism of action and is effective for treating mild to moderate depression. SJW is well tolerated, available over the counter, and is significantly less expensive than the established treatments for tobacco dependence. To date, no prospective clinical trial evaluating the efficacy of SJW for the treatment of tobacco use has been published. We propose to evaluate the efficacy of SJW for increasing tobacco abstinence and decreasing nicotine withdrawal symptoms in a randomized, double-blind, placebo-controlled, three-arm, parallel group, dose-ranging clinical trial. Participants (N=120) will be randomly assigned to one of the three groups and will receive a twelve-week course of SJW 900 mg per day, 1800 mg per day, or a matching placebo. This study is anticipated to provide the data needed to develop a larger randomized controlled clinical trial submitted through the R01 funding mechanism.

Primary Outcome

Point prevalence tobacco abstinence was adjudicated if the following conditions were met:(a) self-reported tobacco abstinence for the previous 7 days with a negative response to the question "Have you used any type of tobacco,even a puff, in the past 7 days?" and (b) Expired Carbon Monoxide equal or less then 8 parts per million.

Interventions

• DRUG Placebo
• DRUG St. John's Wort-900 mg/day
• DRUG St. John's Wort-1800mg/day