title: Torsades de pointes with high-dose loperamide.
abstract: A 41year-old male presented with torsades de pointes. The patient was taking over 100mg of loperamide per day to self-medicate for chronic pain. Coronary angiography, cardiac magnetic resonance imaging, and genetic testing were negative for pre-disposing ischemia, cardiomyopathy, or genetic variant respectively.
  
  
  
  Patients without predisposing genetic or cardiac abnormalities are at risk of life-threatening QTc prolongation and torsades with use of high-dose loperamide. The authors suggest consideration of regulating the quantity of loperamide that can be purchased at a single time similar to the regulations in place for other over-the-counter medications with high potential for misuse.
authors.affiliation: Department of Internal Medicine, Vanderbilt University Medical Center, 1161 21st Avenue South, D-3100 Medical Center North, Nashville, TN. Electronic address: patrick.m.kozak@vanderbilt.edu.
authors.forename: Patrick M
authors.initials: PM
authors.lastname: Kozak
authors.affiliation: Department of Internal Medicine, Vanderbilt University Medical Center, 1161 21st Avenue South, D-3100 Medical Center North, Nashville, TN.
authors.forename: Amanda E
authors.initials: AE
authors.lastname: Harris
authors.affiliation: Department of Internal Medicine, Vanderbilt University Medical Center, 1161 21st Avenue South, D-3100 Medical Center North, Nashville, TN.
authors.forename: John A
authors.initials: JA
authors.lastname: McPherson
authors.affiliation: Department of Internal Medicine, Vanderbilt University Medical Center, 1161 21st Avenue South, D-3100 Medical Center North, Nashville, TN.
authors.forename: Dan M
authors.initials: DM
authors.lastname: Roden
mesh_terms: D000328:Adult; D059350:Chronic Pain / Q000150:complications / Q000188:drug therapy*; D003937:Diagnosis, Differential; D004305:Dose-Response Relationship, Drug; D004562:Electrocardiography / Q000379:methods; D006801:Humans; D008139:Loperamide / Q000008:administration & dosage* / Q000009:adverse effects*; D008297:Male; D012651:Self Medication / Q000009:adverse effects*; D016171:Torsades de Pointes / Q000139:chemically induced* / Q000175:diagnosis* / Q000517:prevention & control
chemical_list: D008139:Loperamide