Chantix may be too dangerous for bus drivers and truckers, and officials should consider not certifying those who are taking the smoking-cessation drug. The statement by the Federal Motor Carrier Safety Administration (FMCSA) comes on the heels of a study that linked Chantix to a host of problems, including traffic accidents. It is just the latest problem linked to the Pfizer drug, which has also been linked to psychological side effects, including suicidal thoughts and behavior.

Last week, the non-profit Institute for Safe Medication Practices issued a report detailing Chantix adverse event repots to the Food & Drug Administration (FDA). The report specifically cited 224 reports of potential heart-rhythm disturbances, 372 reports of possible movement disorders and 544 reports of likely glycemic problems, including diabetes. There were also reports of a dozen traffic accidents linked to Chantix. The Institute’s report has already gotten the attention of the Federal Aviation Administration, which has banned its use by pilots and air traffic controllers.

Now, the FMCSA, a division of the Department of Transportation, is warning bus and truck drivers to stay off Chantix. In a statement, the FDCSA told CBS 11 in Texas that “… it appears that medical examiners should not certify a driver taking Chantix because the medication may adversely affect the driver’s ability to safely operate a commercial motor vehicle.”

Chantix, approved in the US in 2006, works by blocking nicotine receptors to the brain. Chantix is the first such nicotine receptor partial agonist approved by the FDA. It was heralded as an alternative to other smoking cessation drugs and nicotine replacement therapy.

Since its approval, Chantix has been the subject of a number of safety concerns. Chief among them is its apparent link to suicidal thoughts and behavior. Last year, in a Nov. 20 Early Communication, the FDA said that a preliminary assessment of Chantix suicide reports revealed that many of the cases reflected new-onset of depressed mood, suicidal ideation, and changes in emotion and behavior within days to weeks of initiating Chantix treatment. In February, the FDA said “it appears increasingly likely that there may be an association between Chantix and serious neuropsychiatric symptoms.” The agency said that it had asked Pfizer to elevate the prominence of safety information regarding suicidal thoughts and other psychiatric problems to the warnings and precautions section of the Chantix prescribing information, or labeling.