FDA Warns Chantix May Cause Seizures or Change How Users React to Alcohol
The U.S. Food and Drug Administration (FDA) is warning that a prescription drug to help people quit smoking can change the way people react to alcohol. In addition, rare accounts of seizures in patients treated with Chantix have been reported.
The FDA has approved changed to the Chantix label to warn patients about these risks. Until patients know how Chantix affects their ability to tolerate alcohol, they should decrease the amount of alcohol they drink. Patients who have a seizure while taking Chantix should stop the medicine and seek medical attention immediately.
Millions of Americans have serious health problems caused by smoking, which can be reduced by quitting. Chantix is a prescription medicine that is FDA-approved to help adults quit smoking. In clinical trials, Chantix increased the likelihood of quitting smoking for as long as one year compared to treatment with a placebo, an inactive treatment.
The FDA reviewed the case series submitted by Pfizer, the manufacturer of Chantix, as well as the cases in the FDA Adverse Event Reporting System (FAERS) database describing patients who drank alcohol during treatment with Chantix and experienced adverse reactions. Some patients experienced decreased tolerance to alcohol, including increased drunkenness, unusual or aggressive behavior, or they had no memory of things that happened.
The FDA also reviewed FAERS and the medical literature for cases of seizures with Chantix and identified cases in which the patients who had seizures while taking Chantix either had no history of seizures or had a seizure disorder that had been well-controlled. In most of these cases, the seizures occurred within the first month of starting the drug. Information about these risks has been added to the Warnings and Precautions section of the drug label and to the patient Medication Guide.
The FDA also updated the Warnings and Precautions section of the label to include information about several studies that investigated the risk of neuropsychiatric side effects on mood, behavior, or thinking occurring with Chantix. These included observational studies, as well as analyses that Pfizer conducted of randomized controlled clinical trial data. These studies did not show an increased risk of neuropsychiatric side effects with Chantix; however, they did not examine all types of neuropsychiatric side effects, and they had limitations that prevented us from drawing reliable conclusions.
The FDA previously communicated about possible serious neuropsychiatric side effects with Chantix in 2009 and 2011, and these recent studies were discussed at an FDA Advisory Committee meeting in October 2014. Pfizer is conducting a large clinical safety trial of Chantix to investigate this risk and results from this study are expected in late 2015. We will update the public as appropriate when this new information becomes available.
Health care professionals and patients are encouraged to report side effects involving Chantix to the FDA MedWatch program.