Varenicline (Champix) is a partial agonist to nicotine receptors, and is approved for smoking cessation therapy. However, the FDA has raised concern about a possible increase in the incidence of cardiovascular events of patients taking the drug in randomised trials. In this meta-analysis, Prochaska et al. looked at 22 randomised controlled trials of current tobacco users and compared cardiovascular events in those given varenicline compared to those given placebo. Cardiovascular adverse events were defined if they occurred during drug treatment or within 30 days of discontinuation. All the trials included in the analysis were double blind and placebo controlled, and two included participants with active cardiovascular disease, while eleven enrolled patients with a history of cardiovascular disease. Rates of cardiovascular serious adverse events were 0.63% in the varenicline groups and 0.47% in the placebo groups. The summary estimate for the risk difference (0.27%, P=0.15) was not significant either clinically or statistically.<\/p>\n