WASHINGTON (CNN) -- Two popular anti-smoking drugs will now carry warnings about the risk of severe mental health problems, the Food and Drug Administration announced Wednesday. "Smoking is the leading cause of preventable disease, disability and death," an FDA official said. The FDA said Chantix and Zyban will carry the warnings to alert consumers to the risks of depression and suicidal thoughts when using the drugs. The drugs also have been reported to cause changes in behavior, hostility and agitation in users, whether users had a history of psychiatric illness or not. In many cases, side effects started shortly after use began and ended when the medication was stopped. The FDA does not know what is causing the changes and said people taking these products should be monitored by their doctor.
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FDA: Chantix and Zyban will carry warnings about mental health risks
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Risks include depression and suicidal thoughts when using the drugs
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Drug makers must conduct study how often these serious symptoms occur
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Some symptoms could be the result of nicotine withdrawal
The FDA says that since @placeholder was approved in 2006, the agency has had reports of 98 suicides and 188 attempted suicides.