Is domperidone (antiemetic) safe to use in an infant with a significant cardiac history and influenza?

Domperidone Should Be Avoided in Infants with Significant Cardiac History and Influenza

Domperidone is contraindicated in infants with significant cardiac history due to its risk of QT prolongation and potential for serious cardiac arrhythmias, which could be exacerbated by influenza infection.

Cardiac Safety Concerns with Domperidone

Domperidone, an antiemetic and prokinetic agent, poses significant cardiac risks that make it unsuitable for infants with cardiac history:

• Domperidone causes QT interval prolongation at clinically relevant concentrations 1
• It has a low cardiac safety ratio of 5.25 (far below the minimum safety ratio of 30) 2
• The risk of QT prolongation is particularly concerning in pediatric patients, with pathological QTc intervals noted in infants in limited studies 3
• The medication has been associated with increased risk of sudden cardiac death, particularly at doses above 30 mg per day 4

Special Considerations for Infants with Cardiac History

Several factors make domperidone particularly risky in the scenario described:

1. Pre-existing cardiac conditions: Patients with pre-existing cardiac conditions should avoid domperidone as it may exacerbate underlying cardiac issues 1

2. Influenza infection: Viral infections like influenza can:

   • Cause electrolyte abnormalities
   • Potentially worsen cardiac function
   • Increase metabolic demands on the heart

3. Age-related risk: Infants have immature cardiac conduction systems and may be more vulnerable to QT-prolonging effects

Alternative Antiemetic Options

For an infant with significant cardiac history and influenza requiring antiemetic therapy, consider:

• Ondansetron: May be preferred in limited doses, though it also carries some QT prolongation risk (generally less than domperidone)
• Supportive care: Focus on hydration, small frequent feeds, and managing fever
• Metoclopramide: Could be considered for short-term use (1-2 days) at appropriate weight-based dosing, though it carries risk of extrapyramidal side effects 5

Monitoring Recommendations

If any antiemetic therapy is absolutely necessary:

• Obtain baseline ECG before initiating therapy
• Monitor electrolytes (particularly potassium, magnesium, calcium)
• Implement continuous cardiac monitoring if available
• Avoid concomitant medications that prolong QT interval
• Use the lowest effective dose for the shortest duration possible

Conclusion

The risk-benefit analysis strongly weighs against using domperidone in an infant with significant cardiac history and influenza. The potential for QT prolongation and cardiac arrhythmias outweighs the antiemetic benefit, especially when safer alternatives or supportive measures may be sufficient. The combination of cardiac history and acute illness creates a particularly high-risk scenario for domperidone administration.