What is the recommended treatment and dosage of Nystatin for fungal infections?

Nystatin Treatment and Dosage for Fungal Infections

For fungal infections, nystatin is recommended at a dosage of 100,000 U/mL suspension (4-6 mL four times daily) or 200,000 U pastilles (1-2 pastilles 4-5 times daily) for 7-14 days for oropharyngeal candidiasis, and as a topical powder applied 2-3 times daily for 7-14 days for cutaneous candidiasis. 1, 2

Oropharyngeal Candidiasis

Recommended Dosage

• Adults: 4-6 mL (400,000-600,000 units) of oral suspension four times daily 3
• Children: 4-6 mL (400,000-600,000 units) four times daily 3
• Infants: 2 mL (200,000 units) four times daily 3
• Premature/low birth weight infants: 1 mL four times daily 3

Administration Instructions

• Retain the medication in the mouth as long as possible before swallowing
• For infants and young children, use dropper to place one-half of dose in each side of mouth
• Avoid feeding for 5-10 minutes after administration in infants 3
• Continue treatment for at least 48 hours after symptoms have disappeared and cultures demonstrate eradication of Candida albicans 3

Treatment Duration

• 7-14 days for initial episodes 1
• Continue until clinical improvement is seen 1

Cutaneous Candidiasis

Recommended Treatment

• Nystatin powder applied to clean, dry skin 2-3 times daily until infection resolves (typically 7-14 days) 2
• Particularly effective for intertrigo in skin folds, especially in obese and diabetic patients 1, 2

Key Administration Points

• Keeping the infected area dry is as important as the antifungal treatment itself 1, 2
• Complete the full course of treatment even if symptoms improve quickly 2

Comparative Efficacy

Oropharyngeal Candidiasis

• Fluconazole (100 mg/day for 7-14 days) is superior to topical therapy including nystatin in some studies 1
• In a small pilot study with infants, fluconazole showed 100% clinical cure rate compared to 32% with nystatin suspension 4
• Itraconazole solution (200 mg/day for 7-14 days) is as efficacious as fluconazole 1

Prophylaxis in Neonates

• In nurseries with high rates (>10%) of invasive candidiasis, oral nystatin (100,000 units 3 times daily for 6 weeks) is an alternative to fluconazole in neonates with birth weights <1500g 1

Special Considerations

Immunocompromised Patients

• Nystatin alone is not recommended for prophylaxis or treatment of systemic Candida infections in immunocompromised patients 5
• For severe immunodeficiency, fluconazole is more effective than nystatin in preventing invasive fungal infection (relative risk 0.37) and colonization (relative risk 0.49) 5

Formulation Considerations

• Some commercial nystatin formulations contain sugar, which should be considered when treating patients with diabetes 6
• Nystatin is only used topically due to toxicity with systemic administration 7

Common Pitfalls and Caveats

1. Inadequate drying of affected areas can lead to treatment failure in cutaneous infections 2
2. Premature discontinuation of treatment when symptoms improve but before complete eradication 2
3. Misdiagnosis of bacterial infections as fungal infections 2
4. Failure to address underlying conditions like diabetes or obesity that predispose to recurrent infections 2
5. Relying solely on nystatin for systemic or invasive fungal infections, where systemic antifungals are required 5

For invasive or systemic fungal infections, nystatin is not appropriate, and systemic antifungals such as fluconazole, itraconazole, or amphotericin B should be used based on the specific infection and patient factors 1.