Application of pharmacokinetic-pharmacodynamic modeling in management of QT abnormalities after citalopram overdose. Reply to A. Manini

Sir, Manini et al. express concerns about the algorithm that we developed for the management of cardiotoxicity in citalopram overdose. We respond to their comments as follows:In the algorithm we use “dose estimate” and not “ingested dose”. The difference between the dose amount reported (based on the patient history, tablet counts and other available information) and the dose amount estimated in the modelling ranged from 0 to 75 mg, i.e. the reported dose amount was acceptably reliable [1].Of the three published cases that the authors quote where patients ingested less than 600 mg [2, 3, 4], two did not have an abnormal QT based on the QT nomogram derived from Fossa et al. [5, 6]. Bazett\u27s correction was used in these two cases despite its known overcorrection in patients with fast heart rates. In the third case, a patient was reported to have sinus tachycardia, but absolute QT and RR was not reported, in addition to an uncertainty in the reported dose [2]