Abstract 13799: Loperamide; An Old Drug With Deadly New Consequences
Introduction: Loperamide is an over the counter (OTC) opioid-like antidiarrheal originally presumed to lack central nervous system effects, however recent reports have shown that, at supra-therapeutic doses, loperamide can cross the Blood Brain barrier and have opioid-like effect. In this case series we review the clinical course of two patients with life-threatening arrhythmia secondary to loperamide abuse.
Case One: A 37 year old female with congenital long QT syndrome (LQTS) presented to the emergency room (ER) with syncope; monitoring revealed incessant Torsades des Points (TdP); QTc was 678 msec on 12-lead EKG and electrolytes were normal, and drug screen was negative. She admitted to taking up to 120mg/day of loperamide recently for relief of chronic back pain. Acutely she was administered intravenous magnesium and admitted to the hospital; and over the following six days her QTc gradually trended down to 478 msec (similar to baseline) at which point she was discharged.
Case Two: A 24 year old male with LQTS presented with an episode of TdP during tooth extraction, and continued to have TdP in the ER. He had received anti-emetics (known to cause QT prolongation) prior to his tooth extraction, but also admitted to taking up to 200mg/day of loperamide over the past 1-2 months. In the setting of a modestly prolonged QTc (520 msec), he continued to have TdP refractory to magnesium and required trans-venous overdrive pacing to suppress the arrhythmia over the following 48 hours. He eventually stabilized, and was discharged on hospital day five with a QTc of 474 msec.
Discussion: Referred to as “poor man’s methadone", loperamide has been available OTC since 1988. It is inexpensive (circa $10 for 400 2mg tablets) and universally available, leading to increasing frequency of abuse. It may not be detected on routine drug screening, but its abuse should still be considered in patients with TdP or prolonged QT interval.
Author Disclosures: M. Abdelrahman: None. C. Jones: None. R. Storm: None. K. Zazzali: None. K. Al-Azizi: None. J. Oren: None.
- © 2016 by American Heart Association, Inc.