Evaluating the Impact of Vitamins C And/Or E Treatment on Paraquat-Induced Toxicity in Humans: A Frequentist-Bayesian Meta-Analysis and Brief Systematic Review Publisher

Summary: Can vitamins C and E save lives after paraquat poisoning? A meta-analysis of three studies found no clear mortality benefit; evidence remains limited. #Toxicology #ClinicalResearch

Meamar R ; Satari S ; Mesripour A ; Akbari V ; Karimi R ; Moshiri M ; Bamarinejad F
Source: SN Comprehensive Clinical Medicine Published:2026

Abstract

Background: Paraquat (PQ) is a widely used herbicide with high human toxicity, frequently resulting in fatal outcomes following ingestion or dermal exposure. Despite available treatments, including gastric lavage and antioxidants, mortality rates remain alarmingly high. Objective: To systematically review and meta-analyze the available evidence on the impact of vitamins C and/or E therapy on clinical outcomes (mortality) in human patients with paraquat poisoning. Methods: A comprehensive systematic search was conducted across electronic databases (Cochrane Library, PubMed, Scopus, ISI Web of Knowledge, Google Scholar) from inception to December 2023. Studies were included if they were original human research evaluating vitamins C and/or E in paraquat poisoning with reported mortality outcomes. A Bayesian hierarchical model was employed as the primary analytical approach due to the limited number of eligible studies. A complementary frequentist random-effects meta-analysis was also performed. Results: Finally, 3 studies were included. The pooled mean age was 44.46 years (95% CI: 28.35–60.57) in the intervention group and 42.86 years (95% CI: 24.93–60.80). The estimated proportion of males in the intervention group was 25% (19% − 31%), while in the control group it was 65% (58% − 73%). The Bayesian meta-analysis showed that the mortality rate in the intervention group was not significantly different from the control group OR (95%CrI):1.32 (0.56–4.05). A complementary frequentist random-effects meta-analysis yielded a consistent finding (OR = 0.653, 95% CI: 0.124–3.447, P = 0.616), with substantial heterogeneity (I² = 83.91%, P = 0.002). Conclusion: Adjunctive therapy with vitamins C and/or E does not appear to significantly reduce mortality in patients with paraquat-induced toxicity. However, these findings are constrained by the limited number of studies, small sample sizes, and heterogeneous study designs. Larger, well-designed randomized controlled trials are needed to provide definitive evidence on the impact of vitamin supplementation in paraquat poisoning management. © The Author(s), under exclusive licence to Springer Nature Switzerland AG 2026.