(1516) Case Report: Multiple Organ System Failure Secondary to Presumed Loperamide Toxicity

Introduction: Loperamide is an intestinal mu-opioid receptor agonist that prescribed primarily as anti-diarrheal medication. At toxic doses, it is implicated in major adverse outcomes, with systemic manifestations and mortality. We present a case of loperamide toxicity encountered at our community-based tertiary referral center in January 2023 with pancreatic, renal, pulmonary and cardiac manifestations.

Description: A 27 year old male presented with complaint of bilateral lower extremity swelling and generalized weakness after consuming 96mg of loperamide. Physical examination revealed tachycardia, tachypnea, lower extremity edema, and epigastric abdominal tenderness. Laboratory evaluation showed leukocytosis, severe lactic acidosis, transaminitis, elevated lipase, anion gap metabolic acidosis with compensatory respiratory alkalosis, serum osmolar gap, and acute renal failure. Liver ultrasound with doppler and computer tomography imaging were consistent with pancreatitis. A right heart catheterization was consistent with high-output cardiac failure.
The patient gradually developed hypotension, requiring volume resuscitation and vasopressor support. Despite aggressive management, his respiratory and renal function continued to deteriorate, necessitating mechanical ventilation and acute renal replacement therapy. His distributive shock was thought to be secondary to pancreatitis, with subsequent lactic acidosis as complication from loperamide overuse.
Hematological and biochemical parameters, mentation, urinary indices, and treatment-related complications were carefully monitored throughout his treatment. With supportive management, he was weaned off mechanical ventilation and renal replacement therapy.

Discussion: Loperamide and other non-prescription medication have potential for abuse. Loperamide overdose can lead to multi-organ failure and death. Adverse effects have been reported in literature at doses ranging from recommended therapeutic doses (2-16mg) to 400-1000mg. Reported adverse effects of loperamide overdose include altered mental status, coma, acute pancreatitis, nausea, respiratory failure, electrolyte abnormalities, dysrhythmias, QRS and QTc prolongation. Despite widespread use, few physicians are aware of the toxicity associated with loperamide overdose.