Therapeutic Interventions in Organophosphate Poisoning: An Umbrella Review of Systematic Reviews

INTRODUCTION: Organophosphate (OP) poisoning is a significant global health issue, particularly in tropical regions. Despite established treatments such as atropine and oximes, the effectiveness of other interventions remains uncertain. This umbrella review is a critical synthesis of evidence from systematic reviews and meta-analyses on OP self-poisoning. METHODS: Following the Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines, we conducted a review of systematic reviews and meta-analyses published up to January 2025. Databases searched included PubMed, Epistemonikos, and the Cochrane Library. We performed quality assessment using A Measurement Tool to Assess Systematic Reviews, version 2 (AMSTAR-2), and applied the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to evaluate evidence certainty. RESULTS: Of 416 potential papers identified we assessed 27 for eligibility, of which 19 were included in the review. The papers evaluated 11 different interventions as an adjuvant to atropine. Oximes, although commonly used, showed neither benefit nor harm. The systematic reviews and meta-analyses on gastric lavage, plasma exchange with hemoperfusion, lipid emulsions, magnesium sulfate, penehyclidine, rhubarb, and xuebijing have reported significant reductions in mortality, but the evidence comes from very low-quality studies. Alkalinization was not found to be effective for OP poisoning. Evidence was limited by small sample size, inconsistent protocols, and geographical bias, with many studies originating from China. CONCLUSION: After careful scrutiny of evidence pooled by various systematic reviews and meta-analyses, we found that atropine remains the mainstay of treatment for OP self-poisoning. It may be supplemented with oximes, as recommended by the World Health Organization. Gastric lavage has doubtful efficacy and may even be harmful. Additionally, we recommend against the routine use of penehyclidine, rhubarb, xuebijing, hemofiltration, plasma exchange with hemoperfusion, lipid emulsions, magnesium sulfate, and alkalinization in the management of OP self-poisoning.