A Case Report of Torsade de Pointes and Brugada Pattern Associated with Loperamide Misuse and Supratherapeutic Loperamide Concentrations

  • Mark Simon
    Reprint Address: Mark Simon, MD. Department of Emergency Medicine, Denver Health and Hospital Authority, 777 Bannock Street, MC #0108, Denver, CO 80204.
    Department of Emergency Medicine, Denver Health and Hospital Authority, Denver, Colorado
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  • John Rague
    Department of Emergency Medicine, Denver Health and Hospital Authority, Denver, Colorado

    Rocky Mountain Poison and Drug Safety, Denver Health and Hospital Authority, Denver, Colorado
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      Loperamide, commonly sold under the brand name Imodium® (Johnson & Johnson, Fort Washington, PA), is a widely available, over-the-counter antidiarrheal medication that possesses µ-opioid agonist properties and can have catastrophic cardiac events when misused or abused. Since the start of the opioid epidemic in the United States, there has been an increasing number of case reports and deaths linking loperamide abuse with cardiac events such as torsades de pointes (TdP) and Brugada syndrome.

      Case Report

      This case report presents a 22-year-old man who presented in cardiac arrest from polymorphic ventricular tachycardia consistent with TdP and a Type 1 Brugada pattern after intentional loperamide abuse. We discuss this patient's management and the proposed pathophysiology of these two cardiotoxicities, of which, to our knowledge, no previously published case report has displayed both in the same patient after a supratherapeutic loperamide ingestion.

      Why Should an Emergency Physician Be Aware of This?

      As the prevalence of opioid dependency and misuse has increased, so, too, has the misuse of un-scheduled medications such as loperamide to achieve central nervous system opioid effects. It is important for the emergency physician to know about and understand loperamide-associated cardiotoxicities such as prolongation of the QRS, unmasking of Brugada patterns, QT prolongation, or ventricular dysrhythmias such as TdP to be able to recognize and treat it.


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