By David Gutirrez | Natural News
In response to a request from drug giant Pfizer to remove the “black box” warning on the smoking-cessation drug Chantix, the FDA has decided to not only retain the warning but expand it.
A black box warning is the most severe action the FDA can take against a drug, short of banning it. The current label for Chantix already warns that patients taking the drug may develop aggressive or suicidal behavior. That warning will be expanded to note that the drug has also been linked to reduced alcohol tolerance leading to seizures.
“Until patients know how Chantix affects their ability to tolerate alcohol, they should decrease the amount of alcohol they drink,” and FDA spokesperson said. “Patients who have a seizure while taking Chantix should stop the medicine and seek medical attention immediately.”
Chantix, known generically as varenicline, is a popular smoking-cessation drug first approved by the FDA in 2006. In 2013, pharmacies in the United States filled 1.2 million prescriptions for the drug.
The FDA stands by the effectiveness of the drug, which in initial studies was showed to help 33 percent of patients remain tobacco-free six months after quitting, compared with 14 percent of patients on a placebo.
Concerns about the drug’s side effects surfaced almost immediately. By 2007, experts began raising concern that the drug could cause heart problems, vision problems and psychological disturbances including wild dreams and random violent outbursts. In 2008, the U.S. Federal Aviation Administration decided that concerns about Chantix causing blackouts were severe enough for it to ban commercial airline pilots from taking the drug. Commercial truck drivers have also been prohibited from using it.
In 2009, the FDA concluded that enough evidence existed to warrant a black box warning that taking Chantix (or another smoking-cessation drug, Zyban) could increase the risk of “hostility, agitation, depressed mood, and suicidal thoughts or actions.” This warning, plus evidence that Chantix is even more dangerous than Zyban, has caused the U.S. Veterans Administration (VA) to recommend that Chantix be a drug of last resort, following only the failure of nicotine replacement drugs (such as gum or patches) and Zyban. The VA also recommends that all patients have their mental health evaluated before taking Chantix.
Then in 2011, the FDA concluded that Chantix also increased the risk of heart attacks and other cardiovascular problems, especially among people already in poor cardiovascular health.
Memory loss and seizures
In a concerted effort to salvage the reputation of its blockbuster drug, Pfizer announced in 2011 that it was launching an extensive study into Chantix’s potential side effects, with preliminary results expected in 2017. In 2014, the company was already submitting new information to the FDA and petitioned for the removal of the black box warning.
The FDA rejected Pfizer’s assertion that new data showed no difference in rates of psychiatric problems between Chantix users and users of other smoking-cessation drugs.
“[N]ot all types of neuropsychiatric side effects were examined, and the studies had limitations that prevented the FDA from drawing reliable conclusions,” the FDA concluded.
Instead of removing the warning, the FDA will actually be adding extra warnings about changes to mood, behavior and thinking, including memory loss. The biggest finding was the increased rate of seizures among those with no history of epilepsy, or those whose epilepsy was fully controlled before they started taking Chantix.
“In most of these cases, the seizures occurred within the first month of starting Chantix,” an FDA statement reads. “Information about these risks has been added to the Warnings and Precautions section of the drug label and to the patient Medication Guide.”
This article originally appeared on Natural News.