We thank Greene et al for their comments on our study of citalopram overdoses. They raise a number of issues about the study that we can clarify. We agree that it is difficult to determine how useful QT prolongation is as a predictor of citalopram-induced cardiotoxicity. However, Torsades de Pointes (TdP) has been reported in citalopram overdose and there is a well-known association between QT prolongation and malignant arrhythmias. We have recently shown that the QT nomogram used in our study is a valid approach to assessing an abnormal QT interval and risk of Torsades de Pointes.
Annals of Emergency Medicine Vol. 52, Issue 1, p. 87-88