BACKGROUND: This study was conducted to determine the efficacy of the nicotine patch in smoking cessation when combined with self-help materials, three brief visits, and telephone counseling. METHODS: One hundred fifty-nine healthy volunteers who smoked at least one pack of cigarettes per day and desired to quit smoking were enrolled in a double-blind trial with 6-week treatment and 6-month follow-up periods. After review of self-help materials, subjects were randomly assigned to regimens of nicotine or placebo patches. Subjects wore two patches per day for 4 weeks (25 mg of nicotine per 24 hours), then one patch per day for 2 weeks. Return visits were at the ends of weeks 4 and 6. Telephone counseling was given during weeks 1, 2, 3, and 5. Abstinence at 6 weeks was defined as zero cigarettes smoked for the previous 28 days, verified by exhaled carbon monoxide less than 8 ppm at 4 weeks and 6 weeks. Abstinence at 3 and 6 months was defined as self-report of zero cigarettes since the previous contact, verified by carbon monoxide value at 6 months. RESULTS: Abstinence rates at 6 weeks, 3 months, and 6 months were 29.5%, 21.8%, and 20.5% in the active group, and 8.8%, 3.8%, and 2.5% in the placebo group (P < or = .001 for each comparison), respectively. Skin irritation was the main side effect, causing 1.3% to drop out. CONCLUSION: The nicotine patch is efficacious in smoking cessation over a 6-month period, when combined with only self-help materials, three brief visits, and telephone counseling.