title: Acute propafenone toxicity after two exposures at standard dosing.
abstract: A 72-year-old woman presented with a decreased level of consciousness and hypotension. The initial electrocardiogram demonstrated atrial fibrillation with a wide QRS complex. Her medical history revealed that she had just been started on propafenone. A diagnosis of propafenone toxicity was made and sodium bicarbonate was administered. A rare phenomenon in which toxicity occurred at therapeutic dosing is reported. Acute propafenone toxicity manifests in a wide range of organ systems; in particular, cardiovascular compromise in the form of hypotension, bradycardia and QRS widening can occur. Sodium bicarbonate therapy is advocated to directly counteract the toxic effects of propafenone. In the case described, this treatment resulted in rapid normalization of the QRS duration and stabilization of the hemodynamic profile.
authors.affiliation: Department of Internal Medicine, University of British Columbia, Vancouver, BC, Canada.
authors.forename: Adam
authors.initials: A
authors.lastname: Yeung
authors.forename: David
authors.initials: D
authors.lastname: Shanks
authors.forename: Harjinder
authors.initials: H
authors.lastname: Parwana
authors.forename: Kenneth
authors.initials: K
authors.lastname: Gin
mesh_terms: D000208:Acute Disease; D000368:Aged; D000889:Anti-Arrhythmia Agents / Q000008:administration & dosage / Q000009:adverse effects*; D001281:Atrial Fibrillation / Q000188:drug therapy* / Q000503:physiopathology; D003244:Consciousness Disorders / Q000139:chemically induced* / Q000188:drug therapy / Q000503:physiopathology; D004305:Dose-Response Relationship, Drug; D004562:Electrocardiography / Q000187:drug effects; D005260:Female; D006801:Humans; D007022:Hypotension / Q000139:chemically induced* / Q000188:drug therapy / Q000503:physiopathology; D007262:Infusions, Intravenous; D011405:Propafenone / Q000008:administration & dosage / Q000009:adverse effects*; D017693:Sodium Bicarbonate / Q000008:administration & dosage / Q000627:therapeutic use
chemical_list: D000889:Anti-Arrhythmia Agents; D011405:Propafenone; D017693:Sodium Bicarbonate