Effect of Domperidone on QTc Interval in Term and Preterm Newborns: Is It Really Unsafe?

BACKGROUND: Domperidone is a prokinetic drug widely used in newborns for motility disorders. Sporadic cases of QTc prolongation and ventricular tachyarrhythmia related to intravenous domperidone have been reported. Small studies with variable methodology have reported conflicting effects of oral domperidone on QTc in newborns. OBJECTIVE: To evaluate the effect of domperidone on QTc interval in term and preterm newborns. DESIGN/METHODS: A retrospective analysis of QTc changes in newborns treated with domperidone was performed. Only patients for whom at least 2 ECG recordings were available, one taken while on therapy and one while off therapy, were included. QT interval was measured on lead II according to standard methods and corrected for heart rate by the formula of Bazett. Staistically univariate analysis were performed using paired t-test. Subgroup analysis was performed for preterm and term newborns. RESULTS: Data for 80 patients (mean GA 32wks, BW 1735g) were collected and 91 ECG pairs were available (52 before starting therapy and while on treatment, 39 on treatment and after discontinuation). Domperidone was administered in the mean oral dose of 1.6 mg/kg*d (range 0.8-2.4) at a median postnatal age of 29 days. During therapy mean QTc was 0.394±0.034msec. The dosage of domperidone did not affect absolute QTc values neither QTc variations. In 3 pts QTc exceeded the upper normal limits of 440ms. No episodes of ventricular arrhythmia or life-threatening events were observed. No significant changes in QTc were detected before starting and while on treatment (p=0,52); a slight decrease in QTc was observed after domperidone discontinuation (p=0,03). In the subgroup analysis this effect was only seen in preterm (GA< 36wks, p=0,02) and not in term infants (p=0,7). CONCLUSIONS: Oral domperidone administered in the recommended dose range seems to be safe in preterm and term newborns. In preterm infants minor changes in QTc intervals may be detected but they do not seem to be clinically significant.