Torsades de pointes associated with chlorpromazine: case report and review of associated ventricular arrhythmias.
OBJECTIVE
To present a case of chlorpromazine-associated torsades de pointes, review established cases of ventricular arrhythmias associated with chlorpromazine, and describe the proarrhythmic characteristics of this drug.


METHODS
Articles identified through a search of MEDLINE and IDIS from January 1966-November 2000 and thorough review of the article bibliographies. Patient cases also were identified from a search of the Food and Drug Administration's Adverse Event Reporting System database (November 1997-March 2001). Cases involving intentional overdoses of chlorpromazine were excluded.


RESULTS
In addition to the case reported herein, 12 cases of documented, chlorpromazine-associated ventricular arrhythmias were identified; five had characteristic features of torsades de pointes. Chlorpromazine delayed repolarization and produced electrocardiographic abnormalities; although, whether chlorpromazine induced torsades de pointes through a mechanism of early afterdepolarizations is unclear. Similar to other instances of drug-induced torsades de pointes, concurrent factors such as electrolyte deficiencies may place the patient at increased risk for arrhythmia.


CONCLUSIONS
Chlorpromazine can delay repolarization and produce electrocardiographic abnormalities. These can result infrequently in ventricular arrhythmias and torsades de pointes, particularly in patients with confounding factors.
Hoehns
J D
JD
College of Pharmacy, University of Iowa, Iowa City, USA.
Stanford
R H
RH
Geraets
D R
DR
Skelly
K S
KS
Lee
H C
HC
Gaul
B L
BL
D014150:Antipsychotic Agents / Q000009:adverse effects*; D002746:Chlorpromazine / Q000009:adverse effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D016171:Torsades de Pointes / Q000139:chemically induced* / Q000503:physiopathology; D014693:Ventricular Fibrillation / Q000139:chemically induced* / Q000503:physiopathology
D014150:Antipsychotic Agents; D002746:Chlorpromazine