Torsade de Pointes during Combined Treatment with Risperidone and Citalopram

Introduction

Drug-induced long QT syndrome may be associated with potentially life-threatening arrhythmias of the torsade de pointes (TDP) type. Several drugs have been demonstrated to be potentially associated with abnormal QT prolongation and TDP, particularly antiarrhythmic drugs such as quinidine, propafenone, and procainamide, some antimicrobial and antimalarial drugs like erythromycin, cotrimoxazole, chloroquine, several psychotropic agents, e.g., tricyclic antidepressants and antipsychotics [2] [3]. Factors that increase the risk for TDP include hypokalemia, hypomagnesemia, bradycardia, female gender, left ventricular hypertrophy, and heart failure. Furthermore, increased drug plasma concentrations resulting from drug interactions, renal or liver insufficiency leading to drug accumulation, overdosing and/or intoxication also significantly increase the risk [2]. We report the case of a woman with abnormal QT prolongation and TDP induced by a combination of risperidone and citalopram.

References

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