FDA Warns of Possible Link Between Chantix Therapy and Mood Disturbances

December 14, 2007

chantix.jpgCommentary by Robert Leonard PharmD, Pharmacy Resident New York Harbor Healthcare System

On November 20, 2007 the FDA announced mounting evidence linking varenicline (Chantix®) therapy for smoking cessation with suicidal ideation and erratic and aggressive behavior. The announcement comes in response to post-marketing case reports submitted to the FDA by the makers of Chantix®, Pfizer Inc. Early review of the cases reveal new onset of depressed mood, suicidal thoughts, and changes in emotions or behaviors within days to weeks of starting Chantix® therapy. A direct causal relationship remains limited at this time due to the nature of smoking cessation and the emergence of withdrawal symptoms with or without treatment. Nicotine withdrawal alone has been associated with acute exacerbation of underlying psychiatric disorders. Further confounding the interpretation of these reports is the presence of co-morbid conditions often associated with tobacco use disorder that predispose patients to mood disorders such as alcohol dependence. However, despite these limitations, reported cases include mood disturbances in patients who have no prior history of psychiatric illness and in patients who continue to smoke.

Pfizer Inc. has also submitted case reports to the FDA describing drowsiness associated with Chantix ®that influences the ability to safely drive or operate machinery.

In light of these preliminary findings, the FDA has made three recommendations concerning the use of Chantix® for smoking cessation. The official recommendations reported in the press release by the FDA are as follows:

“Healthcare professionals should monitor patients taking Chantix for behavior and mood changes. Patients taking Chantix should contact their doctors if they experience behavior or mood changes. Patients should use caution when driving or operating machinery until they know how quitting smoking with Chantix may affect them.” (1)

The FDA, in conjunction with Pfizer Inc., will continue to review data concerning the safety of Chantix®, the potential association with mood disturbances and the impact on driving or operating machinery. Patients and healthcare providers are encouraged to report adverse affects with Chantix® to the FDA via the MedWatch Adverse Event Reporting program available online at www.fda.gov/medwatch/report.htm.

1. Food and Drug Administration. Early communication about an ongoing safety review varenicline (marketed as Chantix). Available at http://www.fda.gov/cder/drug/early_comm/varenicline.htm. Accessed November 21, 2007.