Bad Side Effects of Chantix

Chantix (varenicline) is an anti-smoking drug associated with serious side effects. The prescription medication can help with smoking cessation. An FDA panel ruled on July 1, 2009, that Chantix and Zyban should carry "black box" warnings, highlighting the possibility of adverse reactions to the drugs. The manufacturer of the anti-smoking drug, Pfizer, has agreed to comply with the recommendations, designed to warn physicians to remain vigilant about the risk of suicide and behavior changes reported in individuals taking Chantix. Zyban is manufactured by GlaxoSmithKline PLC. Both drugs used to stop smoking are available with prescription.

Is This an Emergency?

If you are experiencing serious medical symptoms, seek emergency treatment immediately.


Side effects associated with the stop- smoking drug Chantix include mood swings, suicide, hostility, aggression, paranoia, hallucinations, panic and confusion. Many patients report inability to sleep and nightmares. Reports of serious side effects prompted the FDA to ban Chantix for use by airline pilots.


Chantix can help with smoking cessation by blocking dopamine receptors in the brain that produce pleasure. Nicotine in cigarettes causes dopamine to be released and is a mechanism related to tobacco dependency.


It is not clear whether nicotine withdrawal or stop-smoking drugs cause the serious side effects that prompted the FDA to recommend the strong warnings regarding Chantix from the manufacturer. According to reports, side effects of Chantix occurred even in conjunction with smoking.


Black box warnings are the strictest. The FDA made a statement that the goal of the warning about serious Chantix side effects is to alert physicians to closely monitor patients taking the anti-smoking drug. Dr. Curt Rosebraugh, director of the FDA's Office of Drug Evaluation, said in a news release, “We are requiring the manufacturers of the smoking-cessation drugs Chantix and Zyban to add a new boxed warning highlighting the risk of serious mental health symptoms with use of these products. 1"


As of July 2009, a total of 98 suicides and 188 suicide attempts with the use of stop-smoking drug Chantix have been reported to the FDA since it was approved in May 2006. Review of data showed that symptoms of depression, thoughts of suicide and other behavioral changes started shortly after the drug was initiated and often stopped when the drug was discontinued. If you or someone in your family is taking Chantix for smoking cessation, it is important to report serious side effects to the prescribing physician. History of depression increases the risk of the most serious side effects of the anti-smoking drug Chantix, which include worsening depression and suicide.