BACKGROUND: Sustained-release bupropion hydrochloride and nortriptyline hydrochloride have been shown to be efficacious in the treatment of cigarette smoking. It is not known whether psychological intervention increases the efficacy of these antidepressants. This study compared both drugs with placebo. It also examined the efficacy of these 2 drugs and placebo with and without psychological intervention. METHODS: This was a 2 (medical management vs psychological intervention) x 3 (bupropion vs nortriptyline vs placebo) randomized trial. Participants were 220 cigarette smokers. Outcome measures were biologically verified abstinence from cigarettes at weeks 12, 24, 36, and 52. RESULTS: Psychological intervention produced higher 7-day point-prevalence rates of biochemically verified abstinence than did medical management alone. With the use of point-prevalence abstinence, both nortriptyline and bupropion were more efficacious than placebo. On rates of 1-year continuous abstinence, the 2 drugs did not differ from each other or from placebo. Psychological intervention did not differ from medical management alone on rates of 1-year continuous abstinence. CONCLUSIONS: Both nortriptyline and bupropion are efficacious in producing abstinence in cigarette smokers. Similarly, psychological intervention produces better abstinence rates than simple medical management. Both drugs, and psychological intervention, have limited efficacy in producing sustained abstinence. The data also suggest that combined psychological intervention and antidepressant drug treatment may not be more effective than antidepressant drug treatment alone.