Summary of the main results
From the three studies on Varenicline, it was found that although it has an effect in the short term, it has no long-term effects (more than 12 weeks). However, the generalizability of the results is limited due to the small sample sizes and the wide confidence intervals of these studies. Therefore, the specific effects of Varenicline remain unclear, and the conclusions should be interpreted prudently.
There were three studies on Naltrexone, and the meta-analysis showed that it had no positive effect on smokers. It is worth pointing out that one of the studies of Naltrexone explored its effectiveness for smoking cessation in light drinkers and heavy drinkers. According to the original study’s explanation, Naltrexone was ineffective for light drinkers but effective for heavy drinkers. However, the present analysis of the 95% confidence intervals showed that Naltrexone had no smoking cessation effect on either type of drinker.
As for Topiramate and Bupropion, the result indicated that neither had a good effect on smoking cessation. However, the smoking cessation effects of these two drugs have been explored in very few studies. As such, the conclusions may change with further studies in the future.
The results showed that there was no significant difference in the occurrence of adverse events between the drug group and the placebo group in general (Table 2). The symptoms occurred equally in people who did or did not receive the drug treatment, so these drugs are considered safe to use. However, clinicians and researchers should also be alert to people who may overreact to these drugs. If a serious adverse reaction occurs, the individual should terminate their participation in the trial.