[Sustainable efficacy of oral varenicline for smoking cessation]

Varenicline (Champix) is an alpha4beta2 nicotinic receptor antagonist that is used orally for treatment of nicotine dependence. We conducted a study to examine the sustainable efficacy of varenicline in smoking cessation. The subjects were 148 outpatients (113 men, 35 women; average age; 54.4 +/- 14.0 years) at 6 different hospitals, and their adverse events were monitored in each hospital. The 4-week continuous abstinence rates of smoking cessation were 17.6%, 75.0%, and 84.6% in groups treated for 4 or fewer weeks, 5 to 8 weeks, and 9 to 12 weeks, respectively, with the rate showing a significant increase according to treatment period. Among 83 patients who had adverse events, the abstinence rates were 76.9%, 92.3%, 54.5%, and 55.6% in an observed (OB) group, a nosotropic medication (NM) group, a dose-reduction (RD) group, and a drug-discontinuation (DC) group, respectively. Among 56 patients with nausea, the respective rates were 80.8%, 100.0%, 61.1%, and 50.0%, respectively, with a significantly higher success rate in the NM group than in the RD or DC groups (each p < 0.05). To sustain the efficacy of varenicline in patients with adverse events, we recommend a therapeutic strategy in which the active nosotropic medicine is administered over 12 weeks at the regular dosage.