Nystatin Dosing for Pediatric Patients
Standard Treatment Dosing
For treatment of oral candidiasis (thrush), nystatin dosing varies by age: infants receive 2 mL (200,000 units) four times daily, while children and adults receive 4-6 mL (400,000-600,000 units) four times daily, with treatment continuing for at least 48 hours after symptoms resolve and cultures are negative. 1
Age-Specific Treatment Recommendations:
- Premature and low birth weight infants: 1 mL (100,000 units) four times daily is effective based on limited clinical studies 1
- Infants: Use dropper to place one-half of dose in each side of mouth, avoiding feeding for 5-10 minutes 1
- Children and adults: Retain preparation in mouth as long as possible before swallowing 1
- Treatment duration: 7-14 days for uncomplicated disease 2, 3
Prophylaxis Dosing in Neonates
For prevention of invasive candidiasis in high-risk neonates, oral nystatin 1 mL (100,000 units) every 8 hours for 6 weeks is recommended specifically for infants with birth weight <1500 g when fluconazole is unavailable or contraindicated. 4, 2
Key Prophylaxis Considerations:
- Target population: Neonates <1500 g birth weight in NICUs where fluconazole availability or resistance precludes its use 4, 2
- Fluconazole is preferred: In nurseries with high rates (>10%) of invasive candidiasis, fluconazole 3-6 mg/kg twice weekly is the first-line prophylactic agent with stronger evidence 4
- Nystatin is second-line: Only recommended when fluconazole cannot be used 4, 2
Important Limitations of Nystatin Prophylaxis:
- Reduces fungal colonization and infection but does not reduce overall mortality 4, 2
- Cannot be administered during ileus, gastrointestinal disease, feeding intolerance, or hemodynamic instability—situations very common in extremely premature infants 4, 2
- Potential concerns for gut damage and necrotizing enterocolitis 4, 2
- Paucity of data in infants <750 grams, the highest-risk group 4
Clinical Efficacy Considerations
When Nystatin is Appropriate:
- Mild oropharyngeal candidiasis: First-line therapy alongside clotrimazole troches 3
- Contraindications to systemic azoles: When fluconazole or other systemic antifungals cannot be used 2, 3
- Prophylaxis in VLBW/ELBW infants: Significantly reduces invasive candidiasis rates (1.8% vs 14.2% without prophylaxis) 5
When to Choose Fluconazole Instead:
For moderate to severe oropharyngeal candidiasis, oral fluconazole 100-200 mg (3 mg/kg) daily for 7-14 days is superior to nystatin and represents the preferred treatment. 3 In a comparative trial, fluconazole achieved 100% clinical cure versus only 32% with nystatin 6
Common Pitfalls to Avoid:
- Don't use nystatin as first-line prophylaxis when fluconazole is available in high-risk NICUs—fluconazole has stronger evidence and mortality benefit 4
- Monitor for hypersensitivity reactions, though rare 2, 3
- Recognize futility in patients with gastrointestinal dysfunction or feeding intolerance where oral administration is impractical 4, 3
- Don't expect mortality reduction with nystatin prophylaxis, only reduction in fungal infection rates 4, 2