Conduction Disturbances and Ventricular Arrhythmias Associated with High- Dose Loperamide

Galen Leung,Diana Altshuler

doi:10.4172/2161-0495.1000309

Abstract

Although loperamide has been widely used for the treatment of diarrhea, there is growing popularity over its abuse potential in alleviating opioid-withdrawal symptoms and achieving euphoria. Toxic levels of loperamide have been associated with life-threatening ventricular tachyarrhythmias and cardiac arrest. We report a case of high-dose loperamide ingestion in a patient presenting initially with unstable bradycardia followed by episodes of polymorphic ventricular tachycardia, and an unmasked Brugada ECG pattern. This is the first such report of the Brugada pattern being unmasked on ECG with loperamide ingestion. The patient stabilized with supportive care without the need for inotropic support. We discuss potential mechanisms of toxicity leading to conduction abnormalities and provide a literature review of all published cases of loperamide toxicity to describe proposed treatment options. Recognition of the abuse potential and hazards of this over-the-counter anti-diarrheal therapy will alert the clinician of associated toxidromes and management strategies.

Highlights

Loperamide is an over-the-counter, peripherally-acting, μ-opioid receptor agonist used for the treatment of diarrhea [1]
A series of recentlypublished cases reveals an association with recreational loperamide use with electrocardiographic derangements including QRS complex and QT interval prolongation thought to be related to sodium channel blockade, and potassium channel blockade, respectively, as well as monomorphic ventricular tachycardia and torsades de pointes (TdP) [3,4,5]
We present a case of high-dose loperamide ingestion leading to bradyarrhythmias, prolongation of the QRS complex and QTc interval, unmasking of Type I Brugada pattern, and episodes of TdP

Summary

Introduction

Loperamide is an over-the-counter, peripherally-acting, μ-opioid receptor agonist used for the treatment of diarrhea [1]. Brugada pattern evident in leads V1-2 (Figure 2) She was admitted to the medical intensive care unit (MICU) for further monitoring and consideration for transvenous pacer insertion for overdrive pacing in case of malignant ventricular tachyarrhythmia. The patient admitted to prior episodes of unheralded syncope over the past years when sober She was discharged from the MICU after 2 days of monitoring and repeat ECG 3 days later was notable for sinus tachycardia at 114 BPM, QRS duration of 82, QTc of 460, with loss of the Brugada pattern. She was offered an inpatient psychiatric admission and further cardiac evaluation, but left against medical advice prior to additional workup

Discussion

Conclusion