Chantix (varenicline) is heavily marketed as an aid to quit smoking, but the product does have disturbing side effects. Now, the FDA has updated the label on Chantix, which includes information about its safety and efficacy in individuals with heart disease or those who have chronic obstructive lung disease.
The last update on chantix follows numerous reports that the drug may be associated with an increased risk of myocardial infarction (heart attack), or lead to development of peripheral vascular disease (3).
The FDA has based its reports on a recent randomized trial of 700 smokers with stable heart disease who received chantix 1 mg twice daily for 12 weeks. These individuals were twice as likely to quit smoking and also remain smoke free for 12 months compared to individual who took the placebo (sugar pill). However, in the same study, it was observed that chantix was also associated with a small but real risk of a heart attack (2).
The new label on chantix also contains information on use of chantix by people who have COPD. Like the heart study, another randomized study revealed that individuals with mild to moderate COPD who took 1 mg of chantix twice a day for 12 weeks were also more likely to quit smoking than those who took the placebo (2).
The side effects of chantix in both studies were similar and included nausea and headache. Other common side effects have included difficulty sleeping and abnormal dreams. Rare reported side effects of chantix include depression and suicidal thoughts (1).
At present, chantix has been approved for 12 weeks use. If smoking cessation has been achieved, it may be continued for another 12 weeks.
The European Medicines Agency just announced that the slightly increased risk of heart disease associated with chantix does not outweigh the potential benefits of the drug in helping people quit smoking. In simple words - you may die from a heart attack before you quit smoking (4).