Use of domperidone to increase breast milk supply: Further consideration of the benefit-risk ratio is required

The statement made by Paul et al1 in their systematic review that “the use of domperidone as a galactagogue is worrisome as drug-induced long QT syndrome occurred mostly in women” is extremely misleading and not reflective of current evidence. To be clear, there is no evidence that the risk of QT interval prolongation associated with the use of domperidone is higher among females.2,3 Not discussed by Paul et al1 are the results of a recent case-control study investigating the risk of serious ventricular arrhythmia and sudden cardiac death associated with the use of domperidone, in which an increased risk was observed only among males (adjusted odds ratio [aOR], 2.23; 95% confidence interval [CI], 1.59-3.13) but not among females (aOR, 1.25; 95% CI, 0.93-1.67).4 Furthermore, an increased risk was observed only among those older than 60 years (aOR, 1.64; 95% CI, 1.31-2.05) and not among those 60 years and younger (aOR, 1.1; 95% CI, 0.35-3.47).4 Also omitted from the review by Paul et al1 is any discussion of a recent randomized, placebo-controlled, double-blind, crossover study evaluating the impact of domperidone on QT prolongation among healthy volunteers aged 18 to 39 years (representing the likely cohort of breastfeeding mothers).5 In the study of volunteers, domperidone was demonstrated to prolong the QT interval among males, but no difference in QT interval was observed among females.5 Taken together, these findings provide evidence of a favorable safety profile of domperidone use in breastfeeding mothers.