Loperamide-Induced Ventricular Arrhythmia and Seizures.

BACKGROUND

Loperamide-induced cardiotoxicity can occur when taken at high doses.

CASE SUMMARY: A 42-year-old man presented with polymorphic ventricular tachycardia after taking 100 to 200 mg of loperamide daily to self-treat opioid withdrawal. The presenting electrocardiogram showed a wide complex rhythm which spontaneously converted to sinus rhythm with a prolonged QT interval. Implantable cardiac-defibrillator therapies treated polymorphic ventricular tachycardia and ventricular fibrillation. Loperamide was discontinued, and he was treated for opioid use disorder.

DISCUSSION: Loperamide can cause cardiotoxic manifestations such as acquired long QT syndrome with associated ventricular arrhythmias and neurologic manifestations such as seizures.

TAKE-HOME MESSAGE: Although loperamide is an over-the-counter medication, life threatening cardiotoxicity and neurotoxicity can occur with high doses.