How many hours before domperidone (motility agent) takes effect in newborns?

Domperidone Onset of Action in Newborns

Domperidone paradoxically increases the number of gastroesophageal reflux episodes in newborns within 8 hours of administration, suggesting it begins working within this timeframe, though not necessarily in a beneficial way. 1

Pharmacodynamics in Newborns

• Domperidone is a prokinetic antidopaminergic drug that affects gastric motility in newborns within hours of administration 1
• In a randomized controlled study using combined multichannel intraluminal impedance and pH monitoring, domperidone (0.3 mg/kg) showed measurable effects on gastric motility within 8 hours of oral administration in newborns 1
• Rather than improving symptoms, domperidone paradoxically increased the number of gastroesophageal reflux episodes compared to baseline (4.06±1.16 vs 2.8±1.42; P=0.001) 1

Gastric Emptying Effects

• In preterm neonates, domperidone significantly reduces gastric emptying time when measured ultrasonographically 2
• The mean antral cross-sectional area half-value time was 47.6 minutes in the domperidone group compared to 68.2 minutes in the control group (p = 0.008), indicating faster gastric emptying within hours of administration 2
• This effect was observed when domperidone was administered at a dose of 0.3 mg/kg every 8 hours for at least 2 days 2

Clinical Considerations and Cautions

• Despite measurable physiological effects within hours, clinical symptomatic improvement may take longer to manifest 3
• In older infants (mean age 7.9 months), significant clinical improvement in reflux symptoms was only observed after several weeks of therapy 4
• A double-blind, placebo-controlled trial found that 4 weeks of domperidone therapy did not result in symptomatic improvement in infants and children with gastroesophageal reflux 3
• The paradoxical increase in reflux episodes in newborns raises concerns about the drug's efficacy in this specific age group 1

Safety Considerations

• The safety profile of domperidone in breastfed infants appears favorable based on limited data, with no adverse effects observed in 85 exposed infants in published studies 5
• However, domperidone has been associated with serious cardiac adverse effects including drug-induced long QT syndrome and sudden cardiac death in adults, particularly women 5
• The benefit-risk ratio of domperidone use in newborns should be carefully considered given these potential serious adverse effects and the paradoxical increase in reflux episodes observed in some studies 1, 5

Practical Recommendations

• When using domperidone in newborns, monitor for physiological effects beginning within 8 hours of administration 1, 2
• Be aware that the drug may initially increase reflux episodes in newborns rather than decrease them 1
• Consider that while physiological effects occur within hours, clinical symptomatic improvement may require more prolonged therapy 4, 3
• Given the limited efficacy data and potential safety concerns, consider non-pharmacological approaches to managing reflux symptoms in newborns when possible 5