Smoking Cessation Drugs Deemed Safe, No Adverse Neuropsychiatric Side Effects

Contrary to popular concerns over adverse neuropsychiatric side effects such as increased agitation, depression, hostility or suicidal behavior, due to smoking cessation drugs, new research shows that there is no significant increase in neuropsychiatric events in patients using these kinds of treatment.

The study, published in the journal The Lancet, was requested by the United States Food and Drug Administration following the rise of concerns about the neuropsychiatric safety and efficacy of varenicline and bupropion.

For the study, researchers examined the safety and efficacy of the aforementioned smoking cessation drugs compared to nicotine patches and a placebo control group. Over 8,000 smokers wanting to quit smoking in 16 countries participated in the randomized, controlled, double-blind trials that ran from November 2011 to January 2015. Half of the participants have psychiatric disorders.

"This is the first study to compare the safety and efficacy of the three first-line smoking cessation aids on the market, head-to-head, in smokers. It's the largest double-blind smoking cessation medication trial to date," said Robert Anthenelli, MD, professor of psychiatry, director of the Pacific Treatment and Research Center at UC San Diego School of Medicine and first author of the study, in a statement.

"And no study has done so in smokers with current or past psychiatric disorders who consume roughly 45 percent of the cigarettes sold in the U.S." Anthenelli added.

The researchers found out that there is no significant increase in serious neuropsychiatric adverse events with varenicline (marketed as Chantix in the U.S.) and bupropion (Zyban) compared to nicotine patches and placebo.

They also discovered that varenicline is more effective in making smokers quit compared to bupropion and nicotine patch. Both bupropion and nicotine patch are more effective than the placebo. Throughout the study, most frequent adverse effects reported by the participants were nausea, insomnia, weird dreams and headaches.

Researchers then noted that smokers seeking to quit smoking should be made aware of the small changes in their mood and psychiatric well-being, regardless of which treatment they decide to undergo.

The study was funded by Pfizer and GlaxoSmithKline, makers of varenicline and bupropion, respectively, and designed in consultation with the FDA.