Researchers conclude that prescription medications Varenciline and Bupropion are more or equally effective as Nicotine patches for smoking cessation, with no overall significant differences in adverse neuropsychiatric effects displayed in both psychiatric and non-psychiatric cohorts
The prescription medications Varenicline and Bupropion have been shown to significantly improve smokers’ chances of long-term cessation. However, there has been substantial concern over the safety of both medications, especially regarding unfavorable neuropsychiatric events such as suicide and aggression. The present study, published in The Lancet, looked to uncover any risks of the medications, and compare the smoking cessation efficacy of both medications when compared with one another, and when compared to nicotine replacement therapy.
The randomized, placebo-controlled, double blind study included 8144 participants, who were smokers between the ages of 18 and 75. Participants must have smoked ten or more cigarettes a day to be eligible. Participants were then divided into non-psychiatric and psychiatric cohorts, based on previous diagnoses of psychiatric disorders. Participants either received a daily dose of Varenicline, Bupropion or a transdermal nicotine patch for 12 weeks, followed by a 12-week non-treatment phase.
The overall incidence of adverse neuropsychiatric events was similar across all four treatment groups (Varenicline, Bupropion, Nicotine patch and placebo). Results showed that there were more adverse events for the psychiatric cohort, than the non-psychiatric cohort. The psychiatric cohort also contained a greater number of participants who displayed suicidal ideation. Those in the psychiatric cohort were more likely to report neuropsychiatric adverse events of all types than those in the non-psychiatric cohort. The descriptions of adverse events experienced were consistent with previous research.
Across cohorts, the most frequent adverse events seen were nausea (25% of all Varenciline users), insomnia (12% of Bupropion users), abnormal dreams (12% of nicotine patch users) and headaches (10% of placebo users). Varenciline showed superior cessation efficacy compared to the placebo, and to both the nicotine patch and Bupropion at the end of treatment. Bupropion showed similar efficacy to the nicotine patch, and superior efficacy versus the placebo. The results found are consistent with there being no increase in neuropsychiatric adverse events in either population of smokers. The study, however, detected a 4 percent increase in the rate of neuropsychiatric adverse events between psychiatric and non-psychiatric cohorts.
Future research can look at the differential effectiveness of treatment methods as a function of the severity of various psychiatric diagnoses. A major limitation presented included the exclusion of “light smokers” that smoke <10 cigarettes a day. The results found in this study provide important new information on which both smokers and health care providers can use to make informed choices regarding which smoking cessation method to select for nicotine dependence. The study concluded that smokers who are psychiatrically stable could use both Varenicline and Bupropion safely. Although Varenicline appears to be the most effective medication available, bupropion and the nicotine patch are also both effective when compared with a placebo.
Written By: Rachel Berkovich, BSc