Evaluation of the effectiveness of Vernonia cinerea for the treatment of smoking cessation: a systematic review and meta-analysis

Abstract

Ethnopharmacological relevance: Vernonia cinerea (VC) has been traditionally used in various cultures for its medicinal properties, including its potential role in smoking cessation. Understanding its efficacy and safety can provide valuable insights for public health strategies in tobacco control. Materials and methods: A systematic review was conducted following PRISMA guidelines to evaluate the efficacy and safety of VC for smoking cessation. We identified randomized controlled trials (RCTs) that compared VC with placebo, alongside behavioral therapy and approved pharmacotherapy for smoking cessation, across health centers. Participants included smokers of any age or gender. Results: Thirteen RCTs from Thailand were included in the review. Ten trials compared VC to placebo, involving 1878 patients (943 receiving VC), with a risk ratio (RR) of 1.51 (95 % CI 1.16 to 1.97; low-quality evidence). However, longer follow-up studies (≥24 weeks) indicated no significant association (RR 0.98, 95 % CI = 0.68 to 1.41; low-quality evidence). There was no clear benefit of VC compared to nicotine replacement therapy or nortriptyline. Non-serious adverse effects included mild and transient symptoms such as tongue numbness, nausea, vomiting, drowsiness, and dizziness. Conclusion: VC appears to be a promising aid for smoking cessation particularly effective in trials with follow-ups under 12 weeks. VC demonstrated a benign safety profile, with no serious safety concerns reported. Further research outside Thailand is essential to fully assess its efficacy and applicability.