Stop-Smoking Aid Chantix Sparks Safety Concerns
Researchers Focus on 26 Reports of Chantix and Aggression or Violence; Drugmaker Says No Cause-Effect Evidence Exists
Chantix: A Closer Look continued...
In a sampling of the cases, the researchers reported that:
- A 24-year-old woman on the drug woke up her boyfriend and started beating him, then attempted to kill herself.
- A 21-year-old woman threatened her mother with a shotgun.
- A 46-year-old man reported he had ''crazy thoughts'' of killing himself and his parents.
- A 42-year-old man punched a stranger while at a bowling alley.
The symptoms typically began soon after starting the drug, Moore and his colleagues say, occurring a median of two days after starting.
They found that when the drug was stopped, the symptoms and other adverse effects resolved in most all cases.
Moore and his colleague note that nearly 40% of patients on Chantix were also on tranquilizers, antidepressants, or antipsychotic drugs, according to the FDA. The adverse events, the researchers write, may be more or less likely when another medication is also being taken.
The acts are not likely part of nicotine withdrawal, the researchers say, as they say the effects aren't noticed in other smoking cessation products. The problems may be confined to a small, susceptible group, they say.
Chantix: Other Views
The new report shouldn't turn people automatically against the drug, says Serena Tonstad, MD, PhD, a professor of health promotion and education at the Loma Linda University School of Public Health in Loma Linda, Calif., who reviewed the report for WebMD.
She has served on the advisory board and has been a consultant for Pfizer.
''I wouldn't advise people not to try it [Chantix] based on this report," she says. "The benefit of quitting smoking is most important.'' And, she says, the drug has proven effective in helping people to quit.
She does agree that people on the drug need to be monitored, and people with bipolar disorder should be especially closely monitored, she says. In her experience, they seem to be more at risk for difficulties than people with other psychiatric problems. ''With depressed people, I like their depression to be controlled before putting them on smoking cessation," she says.
MacKay Jimeson, a spokesman for Pfizer, issued this statement: “Pfizer takes the safety of all of its medicines seriously. All post-marketing reports of adverse events are reviewed by Pfizer, and reported to regulators, including FDA. The currently approved Chantix label contains a boxed warning regarding reports of serious neuropsychiatric events reported in some patients. If these neuropsychiatric symptoms are observed by the physician, patient or caregiver, patients should stop taking Chantix and notify their healthcare provider immediately. There is no reliable scientific evidence demonstrating that Chantix causes these events."
Clinical studies are under way, he says, "to help us further characterize the benefit risk profile of Chantix in different smokers. As studies complete, the results will be published.”
From May, 2006 until late last year, Jimeson says, more than 12 million prescriptions for Chantix had been written worldwide. More than 6 million in the U.S. have been prescribed the drug, according to the drug's web site.