A controlled trial of nortriptyline, sustained-release bupropion and placebo for smoking cessation: preliminary results

Abstract

Purpose and methods: Cognitive behavior therapy (CBT) constitutes the basis of smoking cessation programs. Quitting rates are usually increased by the concomitant use of CBT and pharmacotherapy. There are studies showing the efficacy of bupropion and nortriptyline compared to placebo, but there is just one published comparison between these drugs, unfortunately with low power to detect significant differences. This study was designed to compare the efficacy of bupropion, nortriptyline and placebo in a group of smokers who also received intensive counseling therapy. We conducted a double blind, double-dummy, placebo-controlled trial for smoking cessation that lasted 9 weeks. Patients were randomized to receive nortriptyline 75 mg/day (52 subjects), bupropion 300 mg/day (53 subjects) or placebo (51 subjects). All smokers also received the same intensive cognitive behavior therapy. The target day for quitting smoking was usually day 10. Intensive counseling was provided at baseline, weekly during treatment, and at 10, 13, 16, 20 and 26 weeks. Abstinence was defined as continuous when the subject was not smoking since the target-quitting day (self-report) and had an expired carbon monoxide concentration of 10 ppm or less.

Results: The sustained abstinence rates at 6 months were 21.6% in the placebo group, 30.8% in the nortriptyline group (p = 0.40), and 41.5% in the bupropion group (p = 0.05). The odds ratio was not statistically different for smokers using nortriptyline or bupropion (OR 1.60; 95% CI 0.66-3.86; p = 0.35). The most common adverse events were dry mouth and drowsiness in the nortriptyline group and dry mouth and insomnia in the bupropion group.

Conclusions: Treatment with CBT + bupropion resulted in a better 6-month rate of smoking cessation compared to CBT+nortriptyline or CBT + placebo. Abstinence rate in the nortriptyline group was not statistically different from patients in the bupropion or placebo group.