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Updated: Feb 7, 2026
Implantation of an Isoproterenol Mini-Pump to Induce Heart Failure in Mice
Published on: October 3, 2019
Getting de Pointes Across: Isoproterenol for Refractory Methadone-Associated Torsades de Pointes in Alcohol
Jennifer Wrona1, Carmelita Coca2, Tyson Dietrich3
1Pharmacy Services, Banner Health, Phoenix, USA.
Abstract:
Methadone is known to prolong the QTc interval and may precipitate torsades de pointes (TdP), particularly at higher doses and in the presence of additional risk factors. Standard management involves discontinuation of the offending agent, correction of electrolyte imbalances, and administration of intravenous magnesium; however, some patients may continue to experience recurrent TdP. We present a case of a young female on high-dose methadone, who developed TdP in the context of acute alcohol withdrawal and clonidine-associated bradycardia. Her arrhythmia persisted despite treatment with magnesium and lidocaine but resolved following initiation of an isoproterenol infusion. This case emphasizes the importance of systematic risk assessment in patients receiving methadone and supports the use of isoproterenol as a viable therapeutic option when TdP is refractory to first-line interventions.
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