Pharmacological management of low milk supply with domperidone: separating fact from fiction.

E xclusive breastfeeding for the fi rst 6 months of life is well recognised as the optimal form of nutrition to support the growth and development of term and preterm infants. 1 Whether real or just perceived, low milk supply is the most commonly reported reason for early discontinuation of breastfeeding. 2 This is despite the fact that most mothers are able to produce suffi cient quantities of milk for their baby, if given the correct support and information. 3 Risk factors for women experiencing low milk supply include maternal illness, caesarean birth, maternal smoking, previous breast surgery, mother– infant separation and indirect lactation (ie, breast pump or manual milk expression). 3 Mothers of infants who are unwell and require supportive care after birth, such as preterm infants, are particularly vulnerable to experiencing low milk supply. 3 In many of these situations, non-pharmacological strategies such as optimising infant positioning and attachment at the breast, increasing the frequency of breastfeeds and mechanical expression are usually suffi cient to increase a woman's milk supply. 3 However, some women still struggle to establish or maintain an adequate milk supply. In these situations, pharmacological intervention with medications used to augment lactation, known as galactagogues, is warranted. The most widely studied and commonly used galactagogues are the dopamine receptor antagonists, metoclopramide and domperidone. Both medications stimulate prolactin release by blocking dopamine D2 receptors in the anterior pituitary. Although studies are still few, these drugs have been shown to be effective treatments for the initiation and maintenance of lactation. 4,5 In recent years, domperidone has become increasingly used in preference to metoclopramide, as it does not cross the blood–brain barrier, is associated with fewer central nervous system side effects (ie, fatigue, irritability, depression), and is secreted in only small amounts into breast milk. 4 Recently, albeit not for the fi rst time, warnings surrounding the use of domperidone and the potential for adverse cardiac effects have arisen. 6 However, these warnings require greater scrutiny, as their relevance to young and otherwise healthy lactating women is uncertain. 5 The QT-prolonging effects of domperidone, which place susceptible users at a signifi cantly increased risk of fatal cardiac arrhythmias, have been well known for years. 6 Of particular interest is the concept of susceptibility, as the early case reports linking domperidone use to sudden cardiac death describe the administration of high-dose intravenous formulations in patients with cancer who also …