Primary aim: Will varenicline be better than placebo to get long-term users of NRT to stop?

Secondary aim: To assess in details some side effects of varenicline i.e. nausea and abnormal dreams.

100-200 long-term users of NRT will be enrolled in a placebo, controlled, randomized trial with varenicline or placebo for 12 weeks to stop the use of NRT.

Assessments consist of carbon monoxide in expired air, p-cotinine, body-weight, questions about craving, nausea and dreams. Primary result is percent not using NRT and not smoking at 12 weeks (point prevalence last 7 days) and secondary result is not smoking and not using NRT at 12 months. Secondary aims, is a more detailed assessment of nausea and dreams; well-known side effects of varenicline and secondary results are a qualitative description of nausea and dreams.

Inclusion Criteria:

• Long-term, daily NRT users (except nicotine patch) (>11 months) ex-smokers that are willing to try to stop the use of NRT and adhere to this protocol.
• More than 4 pieces of nicotine gum/ sublingual tablets/ lozenges/ per day, OR more than 3 inhaler cylinders per day, OR
• more than 10 puffs of nasal spray per day.

Exclusion Criteria:

• Age < 18 years,
• CO Smokers,
• Pregnant and lactating women,
• Used varenicline before,
• Not able to cooperate,
• Other significant diseases that might influence the trial (such as moderate -severe cardiac disease, lung cancer,) in expired air > 7 ppm.