What is the recommended dose and frequency of nystatin (antifungal medication) for treating fungal pharyngitis?

Nystatin Dosage for Fungal Pharyngitis

For fungal pharyngitis, nystatin suspension should be administered at a dose of 4-6 mL (400,000-600,000 units) four times daily for 7-14 days. 1, 2

Dosing Recommendations

The recommended dosage of nystatin for oropharyngeal candidiasis (including pharyngitis) is based on high-quality evidence from clinical practice guidelines:

• Adults: 4-6 mL (400,000-600,000 units) four times daily for 7-14 days 1, 2
• Children: 4-6 mL (400,000-600,000 units) four times daily for 7-14 days 1, 2
• Infants: 2 mL (200,000 units) four times daily 2

Administration Technique

For maximum effectiveness:

• The suspension should be divided with half the dose administered to each side of the mouth
• Patient should retain the medication in the mouth as long as possible before swallowing
• Avoid eating or drinking for at least 5-10 minutes after administration
• Continue treatment for at least 48 hours after symptoms have resolved 2

Treatment Considerations

Severity-Based Approach

1. For mild pharyngeal candidiasis:

   • Nystatin suspension (100,000 U/mL) 4-6 mL four times daily, OR
   • 1-2 nystatin pastilles (200,000 U each) four times daily, for 7-14 days 1

2. For moderate to severe disease:

   • Consider oral fluconazole 100-200 mg daily for 7-14 days instead of nystatin, as it has superior efficacy 1

Important Clinical Caveats

• Nystatin works as a topical agent and must make direct contact with the infected tissue
• Treatment should continue for at least 48 hours after clinical symptoms resolve to prevent relapse
• Clinical studies have consistently shown that systemic antifungals (like fluconazole) have higher cure rates and lower relapse rates compared to nystatin for oropharyngeal candidiasis 3, 4, 5
• In immunocompromised patients, fluconazole demonstrated 91% clinical cure compared to 51% with nystatin 5

Treatment Duration

• Standard duration: 7-14 days 1
• Continue treatment for at least 48 hours after symptoms resolve 2
• For persistent or recurrent infections, extending treatment may be necessary

Pitfalls to Avoid

1. Inadequate contact time: Patients often swallow nystatin too quickly, reducing efficacy. Instruct patients to swish and hold the suspension in the mouth for as long as possible.

2. Premature discontinuation: Stopping therapy once symptoms improve but before complete eradication can lead to recurrence. Complete the full course.

3. Underestimating severity: Nystatin is appropriate for mild cases, but moderate to severe infections may require systemic therapy with fluconazole.

4. Ignoring underlying conditions: In immunocompromised patients, addressing the underlying immune dysfunction is crucial for preventing recurrence.

5. Missing drug interactions: Unlike systemic antifungals, nystatin has minimal drug interactions due to its poor systemic absorption, making it safer in patients on multiple medications.