Clinical Toxicology of Sodium Channel Blockers: An Evidence-Based Review for Pharmacists
Abstract
Background: Sodium channel blockers are widely used in cardiology, neurology, and pain management, but their toxicity poses significant risks, including life-threatening arrhythmias and seizures. Understanding their toxicology is essential for pharmacists and clinicians.
Aim: To provide an evidence-based review of the clinical toxicology, pathophysiology, and management strategies for sodium channel blocker toxicity.
Methods: A comprehensive literature review was conducted, synthesizing data from toxicology reports, pharmacologic studies, and clinical guidelines. Epidemiologic trends, mechanistic insights, and therapeutic interventions were analyzed to inform best practices.
Results: Toxicity commonly arises from intentional overdose, medication errors, or drug interactions. Clinical manifestations include QRS widening, ventricular dysrhythmias, seizures, and metabolic acidosis. Tricyclic antidepressants and Class I antiarrhythmics are prominent culprits, with mortality rates reaching 22.5% for antiarrhythmic overdoses. Sodium bicarbonate therapy remains the cornerstone of treatment, effectively reversing conduction abnormalities through alkalinization and sodium loading. Adjunctive measures include hypertonic saline, lipid emulsion for local anesthetic toxicity, and extracorporeal membrane oxygenation (ECMO) in refractory cases. Prevention strategies emphasize safe prescribing, procedural safeguards, and patient education.
Conclusion: Sodium channel blocker toxicity is a high-risk, multisystemic emergency requiring rapid recognition and aggressive intervention. Early ECG monitoring, timely bicarbonate therapy, and coordinated interprofessional care significantly improve outcomes.
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Copyright (c) 2025 Essa Hassan Essa Abu Alzwaid, Mohammed Ali Hussein Alhazmi, Khaled Mohammed Nasser Awlqi, Mossa Ahadad Hakami, Mohammed Mansour Shtefi, Nouf Mohammed Aboishah, Nasser Mohammed Ali Mjrshi, Amany Mohammad Mohammad Sahli, Abdulrahman Yahya Almalki, Hadeel Ali Mohammed Aljohany
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