Novel Therapies for Myocardial Irritability following Extreme Hydroxychloroquine Toxicity

Abstract

Introduction. Hydroxychloroquine (HCQ) overdose is rare and potentially deadly when consumed in large doses. Management of severe HCQ toxicity is limited and infrequently reported. This report presents the case of a massive ingestion of HCQ. Case Report. A 23-year-old female presents following an intentional ingestion of approximately 40 g of HCQ. Within six hours after ingestion, she developed severe hemodynamic instability resulting from myocardial irritability with frequent ventricular ectopic activity leading to runs of polymorphic ventricular tachycardia (PMVT) and ventricular fibrillation (VF) requiring multiple defibrillations. Additional treatments included intravenous diazepam, epinephrine, norepinephrine, sodium bicarbonate, and magnesium sulfate. Despite the ongoing hemodynamic instability, the patient was also treated with Intralipid (ILE) and received hemodialysis. Improvements in her hemodynamics were observed after 18 hours. She survived her massive overdose of HCQ. Conclusion. HCQ poisoning is rare but serious because of its rapid progression to life-threatening symptoms. Hemodynamic support, gastric decontamination, electrolyte monitoring and replacement, and management of arrhythmias are the mainstays of treatment. The combined role of dialysis and ILE in the setting of massive HCQ overdose may improve outcomes.

Acute chloroquine and hydroxychloroquine toxicity: A review for emergency clinicians

“…Aminoquinoline overdose produces toxicity ranging from mild to severe. Unlike with chloroquine overdoses, there is no established lethal or toxic dose of hydroxychloroquine in adults, and management should be tailored to observed toxicity [ 22 ]. Mild chloroquine toxicity in adults is defined as symptomatology occurring with suspected ingested dose <2 g, normal systolic blood pressure, and normal QRS (≤120 ms) [ 19 ].…”

“…Doses exceeding 5 g are highly associated with mortality due to arrhythmias and hypokalemia [ 94 ]. Treatment in the ED setting is focused on high-quality symptomatic and supportive measures, decontamination, stabilization of cardiac dysrhythmias if present, hemodynamic support, and electrolyte correction as necessary [ 22 ]. Indications for intensive care unit admission include persistent systemic hypotension, QRS elongation >120 ms, ventricular arrhythmias, seizures, coma, and persistent hypoglycemia [ 95 ].…”

“…Prospective clinical trials evaluating treatment are also rare and date back to the 1980s and 1990s [ 20 , 21 ]. Updated treatment recommendations for aminoquinoline toxicity since the development of rescue modalities including intravenous lipid emulsion (ILE) and extracorporeal membrane oxygenation (ECMO) are lacking [ 22 ]. This article reviews the pathophysiology of aminoquinoline toxicity to provide guiding principles for management of acute complications.…”

Intentional Hydroxychloroquine Overdose Treated with High-Dose Diazepam: an Increasing Concern in the COVID-19 Pandemic

“…Given its large volume of distribution and significant protein binding, hydroxychloroquine is not amenable to clearance via hemodialysis [18]. Intravenous lipid emulsion (ILE) has also been suggested as treatment, by acting as a "lipid sink" and redistributing lipophilic hydroxychloroquine from tissues into the plasma [9,19]. However, ILE may exert a paradoxical effect by pulling toxins out of the gut and increasing their systemic circulation.…”

Accidental hydroxychloroquine overdose resulting in neurotoxic vestibulopathy

“…First, a patient should immediately report to the nearest emergency department for a full evaluation. The cornerstone of treatment for hydroxychloroquine overdose includes close cardiac monitoring for stabilisation and evaluation of arrhythmias, haemodynamic support for potential hypotension and myocardial depression, electrolyte balance in the setting of hypokalaemia, and gastric decontamination with activated charcoal and lavage if presenting within the first hour of overdose 17. Furthermore, recent literature also supports the life-saving benefit of intravenous lipid emulsion to block cardiotoxicity in hydroxychloroquine poisoning 18…”