Varenicline: new drug. Smoking cessation: no better than nicotine

(1) Drugs play a limited role in smoking cessation. Nicotine is the drug with the best risk-benefit balance and is available in several formulations and dose strengths. However, only about 16% of patients remain abstinent after one year, compared to about 10% of patients on placebo. Bupropion, an amphetamine derivative, is best avoided. (2) Varenicline, a partial acetylcholine receptor agonist, has been approved as an aid in smoking cessation. There are no published trials of varenicline versus nicotine. (3) Four placebo-controlled trials show that after 12 weeks of treatment with varenicline about 22% of patients remain abstinent at one year, compared to 8% on placebo. In the two trials also including a group treated with bupropion, the one-year abstinence rate was significantly higher with varenicline than bupropion in one trial and also in a combined analysis of the two trials. (4) The known adverse effects of varenicline seem to be limited in scope. In the short term they mainly consist of gastrointestinal problems (especially nausea and constipation) and neuropsychological disorders (insomnia, dream disturbances, and headache). Long-term cardiac toxicity cannot currently be ruled out. Simultaneous use of nicotine and varenicline aggravates the adverse effects of nicotine. (5) In practice, varenicline does not appear to have a better risk-benefit balance than nicotine. Nicotine therefore remains the first-choice drug when a patient needs pharmacological support to stop smoking.