Conduction Disturbances and Ventricular Arrhythmias Associated with High- Dose Loperamide

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.