Loperamide-Induced Torsades de Pointes

Loperamide is a readily available, over-the-counter medication used to treat diarrhea. At therapeutic doses, loperamide exerts its effects mainly on the intestinal opioid receptors with minimal psychoactive effects; however, at supratherapeutic doses, it reaches central opioid receptors. With tighter regulations on opioid prescriptions, loperamide has emerged as a popular drug of abuse among opioid users. At supratherapeutic doses, loperamide can cause severe cardiac toxicity, resulting in wide QRS rhythms, severe bradycardia, prolonged QTc, polymorphic ventricular tachycardia, and cardiac arrest. We present the case of a 27-year-old female with a history of heroin abuse who suffered torsades de pointes resulting in cardiac arrest in the setting of a loperamide overdose.