Chantix Under Fire

Smokers who use Pfizer’s Chantix to help them quit are at higher risk for heart trouble, seizures, and diabetes, according to a recent report from the Institute for Safe Medication Practices. The institute’s study reviewed adverse-event reports received by the FDA and found 988 serious incidents linked to Chantix in the US in the fourth quarter of last year—the highest number of reports for any drug during that period. The study’s authors called on Pfizer to strengthen the label warnings for Chantix, claiming that the current warnings are inadequate.

Pfizer claims that the number of incidents related to Chantix is not out of line, since more than 5.5 millions Americans have taken the drug. The FDA, while acknowledging the potential safety issues raised by the report, says that it is focusing for now on the possible adverse psychiatric side effects of Chantix, which has also been linked to suicide and depression. However, the drug has recently been in the crosshairs of more than one regulatory agency. The Federal Motor Carrier Safety Administration recently advised medical examiners not to approve anyone using Chantix for a commercial driver’s license, while the FDA issued a warning about the use of Chantix to pilots and air traffic controllers, advising pilots not to fly within 72 hours of taking the drug.

The almost 1,000 incidents reviewed for the ISMP report include falls and traffic accidents, possibly due to dizziness, confusion, or muscle spasms, as well as arrhythmias and glycemic problems. The study also notes that most drugs that receive anywhere near the number of adverse-incident reports that Chantix has drawn carry the FDA’s most serious “black box” warning label.