Topiramate and Bupropion
Two RCTs[34, 36] involving 223 smokers reported the smoking cessation effects of Topiramate. The results of the meta-analysis showed that Topiramate had no obvious smoking cessation effects (OR = 1.56, 95% CI: [0.67, 3.64], p = 0.31; Figure 5). As for Bupropion, only one RCT[29] was included. The results of the original study showed that the difference between the two groups was not statistically significant in the fourth (p = 0.28) or ninth (p = 0.44) week of treatment or after six months (p = 0.28). Bupropion did not increase the smoking cessation rate.
Adverse events
A detailed analysis of the possible damaging effects to the body caused by these drugs was made based on the adverse reactions reported in the included studies. As shown in table 2, the four drugs may cause side effects, including vomiting, nausea, diarrhea, headache, dry mouth, sweating, insomnia, and dizziness. The difference in adverse reactions between the drug treatment and placebo groups was tested based on the value of the odds ratios (OR), the 95% confidence intervals, and the p-value. With the exception of two studies[29] that reported Naltrexone could cause more adverse events, the other studies all showed that there were no significant differences in the occurrence of adverse events between the treatment and control groups.