What is the next step in treating thrush (oral candidiasis) that is not responding to nystatin?

Management of Thrush Not Controlled with Nystatin

For oral candidiasis (thrush) not responding to nystatin, fluconazole 100-200 mg daily for 7-14 days is the recommended next step treatment. 1, 2

Treatment Algorithm for Refractory Oral Candidiasis

First-Line Alternative After Nystatin Failure

• Fluconazole: 100-200 mg (3 mg/kg) daily for 7-14 days 1, 2, 3
  • Advantages: High efficacy rate, convenient once-daily dosing
  • Evidence shows superior clinical cure rates compared to nystatin in multiple studies 4

Second-Line Options (If Fluconazole Fails)

1. Itraconazole oral solution: 200 mg daily for 7-14 days 1, 5

   • Should be vigorously swished in the mouth before swallowing
   • For fluconazole-refractory cases: 100 mg twice daily 5

2. Posaconazole: 400 mg twice daily for 14 days 1

   • Particularly effective for resistant Candida species

3. Echinocandins (for severe refractory cases): 1, 2

   • Caspofungin: 70 mg loading dose, then 50 mg daily
   • Micafungin: 100 mg daily
   • Anidulafungin: 200 mg loading dose, then 100 mg daily
   • Note: Parenteral administration required

Considerations for Treatment Selection

Factors Affecting Treatment Choice

• Severity of infection: More severe cases may require systemic therapy
• Suspected resistance: Consider C. glabrata or other non-albicans species
• Patient factors: Immunosuppression, ability to tolerate oral medications
• Drug interactions: Azoles have significant drug interaction potential

Why Nystatin May Fail

• Limited contact time with oral mucosa 6
• Resistance development in Candida species
• Poor patient adherence due to taste and frequent dosing requirements
• Suboptimal formulation (suspension vs. pastilles)

Special Considerations

Immunocompromised Patients

• May require longer treatment durations
• Consider maintenance therapy to prevent relapse
• More aggressive initial therapy may be warranted

Prevention of Recurrence

• Address underlying risk factors:
  • Good oral hygiene
  • Proper denture care if applicable
  • Rinse mouth after using inhaled corticosteroids
  • Control of underlying conditions (diabetes, etc.)

Common Pitfalls to Avoid

1. Continuing ineffective nystatin therapy for too long
2. Not considering resistant Candida species
3. Inadequate treatment duration
4. Failure to address underlying predisposing factors
5. Not considering drug interactions with azole antifungals

Fluconazole has demonstrated significantly higher clinical cure rates compared to nystatin in direct comparative studies, with one pediatric study showing 100% cure with fluconazole versus only 32% with nystatin 4. The evidence strongly supports switching to fluconazole as the next step when nystatin fails to control oral thrush.