What is the recommended dose of nystatin?

Nystatin Dosing Recommendations

For oral thrush in adults and children, use nystatin suspension 4-6 mL (400,000-600,000 units) four times daily for 7-14 days, or alternatively nystatin pastilles 1-2 tablets (200,000 units each) four times daily for 7-14 days. 1

Dosing by Clinical Indication

Oral Candidiasis (Thrush) - Adults and Children

• Suspension formulation: 4-6 mL (400,000-600,000 units) four times daily for 7-14 days 1
• Pastille formulation: 1-2 pastilles (200,000 units each) four times daily for 7-14 days 1
• Administration technique: Swish thoroughly in mouth for at least 2 minutes before swallowing to ensure contact with all affected areas 1

Neonatal Prophylaxis (Invasive Candidiasis Prevention)

• Dose: 100,000 units three times daily for 6 weeks 2
• Target population: Neonates with birth weights <1500 g in settings where fluconazole is unavailable or resistance precludes its use 2
• Important caveat: This is a weak recommendation with moderate-quality evidence, as fluconazole prophylaxis is preferred when available 2

Treatment Algorithm by Severity

Mild Oral Thrush

• First-line: Nystatin suspension 4-6 mL four times daily for 7-14 days 1
• Continue full course even if symptoms improve earlier 1

Moderate to Severe Oral Thrush

• First-line: Oral fluconazole 100-200 mg daily for 7-14 days is more effective than nystatin 1
• Nystatin should be reserved for mild cases or when fluconazole is contraindicated 1

Important Clinical Considerations

Efficacy Limitations

• Nystatin suspension is inferior to fluconazole in infants, children, and HIV/AIDS patients with oral candidiasis 3, 4
• In one study, clinical cure rates were only 32% with nystatin versus 100% with fluconazole in infants 3
• Pastilles are more effective than suspension alone when treating oral candidiasis 4

Optimizing Treatment Success

• Combination therapy: Using nystatin pastilles and suspension together for 2 weeks may achieve higher cure rates than suspension alone 4
• Higher pastille doses: 400,000 IU pastilles result in significantly higher mycological cure rates than 200,000 IU 4
• Extended duration: Treatment with pastilles for 4 weeks appears more effective than 2 weeks 4

Special Populations

Neonates <750 grams: Limited data exist for this highest-risk group; nystatin may not be administrable during ileus, gastrointestinal disease, feeding intolerance, or hemodynamic instability 2

Denture-related candidiasis: Denture disinfection must accompany nystatin therapy for successful treatment 1

HIV-infected patients with recurrent infections: Antiretroviral therapy is strongly recommended to reduce recurrence rates; systemic therapy may be more appropriate than topical nystatin 1

Safety Profile

• Common adverse effects: Poor taste and gastrointestinal upset are most frequent 4
• High-dose tolerance: Oral doses exceeding 5 million units daily have caused nausea and gastrointestinal upset, but no serious toxic effects have been reported 5
• Relapse rates: Nystatin is associated with higher relapse rates compared to azole antifungals 6

Common Pitfalls to Avoid

• Inadequate contact time: Patients must swish suspension for at least 2 minutes before swallowing, not just briefly rinse 1
• Premature discontinuation: Complete the full 7-14 day course even when symptoms resolve early 1
• Using nystatin for moderate-severe disease: Systemic fluconazole is significantly more effective for anything beyond mild thrush 1
• Ignoring dentures: Failure to disinfect dentures will lead to treatment failure in denture stomatitis 1