November 3rd, 2011
10:56 AM ET
The popular quit-smoking drug Chantix may increase the risk of suicide and suicidal thoughts in some patients, says a new report.
Researchers looked at more than 3,000 reports of "neuropsychiatric adverse events" - unexpected problems that result in risk or harm to the patient -relating to smoking cessation drugs, and found that more than 90% of the reports were associated with Chantix use.
"We compared people who took nicotine replacement therapy, Zyban and Chantix," said Dr. Curt Furberg, a study author, and professor of public health sciences at Wake Forrest Baptist Medical Center. "There was an increase in suicides even with nicotine replacement therapies, but Chantix was 8-10 times worse."
[The FDA report] looked at hospitalized events," he said. "82% of all serious adverse events do not lead to hospitalization, so that means they missed 82% of all of the serious adverse events."
And though the FDA makes this very same point on its own report, the agency says the drug is safe when used appropriately.
"We continue to believe that when used as directed in the currently approved labeling, Chantix is a safe and effective treatment to help patients stop smoking," FDA spokeswoman Karen Riley said in an email to CNN.
Concerning reports about the drug's safety are nothing new. Since it was approved in 2006, Chantix has been banned by the Federal Aviation Administration for use in pilots, because of concerns about possible blackouts. The U.S. military also has banned the drug for pilots, air-traffic controllers and missile teams; its use has been tightly controlled among truck drivers for similar reasons.
Since 2009, Chantix and Zyban have been required to carry "black box" warnings on their packaging, noting risks of depression and suicide.
Earlier this year, another report by Furberg and his associates found a 72% increased risk of serious cardiovascular events in Chantix users. Other previous studies have shown a link between the drug and an increase in violent and aggressive behavior.
Pfizer, the drug company that makes Chantix, said in a statement to CNN that any reports of suicidal behavior do not necessarily implicate the drug.
"It is important to remember that post-marketing reports do not establish a cause and effect relationship," wrote MacKay Jimeson, a drug company spokesman. He went on to cite the FDA's statement last week that “the agency continues to believe that the drug’s benefits outweigh the risks and current warnings in the Chantix label are appropriate.”
Furberg and his co-authors are calling on the FDA to change warning labels for Chantix, and say the drug may not be the best first-line defense against smoking.
"If you're going to use Chantix, it should be the last resort," Furberg said, "and even then you need to monitor a patient's mental status. That’s a reasonable policy, and we'd like the FDA to do that."
Furberg went onto say that people taking the drug now should talk with their doctor to determine whether Chantix is the best quit-smoking aid for their particular needs.
According to Pfizer's website, more than 7 million people in the United States have been prescribed Chantix since it was approved in 2006.
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