A large Cochrane living systematic review including 90 studies and over 29,000 participants found that nicotine-containing electronic cigarettes (ECs) are more effective for long-term smoking cessation than nicotine replacement therapy (NRT) or non-nicotine ECs. Nicotine ECs increased quit rates by 59% compared with NRT and by 46% compared with non-nicotine ECs, with most reported adverse events mild and transient, such as throat irritation and cough. Serious adverse events were rare, and current evidence does not indicate differences in serious harms between nicotine ECs and other cessation approaches, though estimates remain imprecise due to low event rates.
Compared with behavioral support or no support, nicotine ECs may further increase quit success, although certainty is lower due to study bias. The review found little to no difference in adverse event rates between nicotine and non-nicotine ECs or between nicotine ECs and NRT, with insufficient evidence to determine differences in serious adverse events. Overall, while nicotine ECs show clear benefits for achieving smoking abstinence, longer and larger trials are needed to fully assess safety, especially for long-term use and in comparison with newer or illicit vaping products.
Keywords: electronic cigarettes, smoking cessation, nicotine vaping, tobacco harm reduction