What is the recommended treatment for oral candidiasis using oral nystatin?

Oral Nystatin for Oral Candidiasis

For mild oral candidiasis, use nystatin suspension 4-6 mL (400,000-600,000 units) four times daily for 7-14 days, but for moderate-to-severe disease or immunocompromised patients, oral fluconazole 100-200 mg daily is superior and should be used instead. 1, 2

Treatment Algorithm by Disease Severity

Mild Oral Candidiasis

• First-line: Nystatin suspension (100,000 U/mL) at 4-6 mL four times daily for 7-14 days 1, 3, 2
• Alternative formulation: Nystatin pastilles (200,000 U each), 1-2 pastilles 4-5 times daily for 7-14 days 1, 3
• Clotrimazole troches (10 mg, 5 times daily) are equally effective as an alternative topical option 1

Moderate-to-Severe Oral Candidiasis

• First-line: Oral fluconazole 100-200 mg daily for 7-14 days is superior to nystatin and should be used preferentially 1, 2, 4
• Fluconazole achieves 87% clinical cure versus only 52% with nystatin in HIV-infected patients 4
• Itraconazole solution 200 mg daily for 7-14 days is equally efficacious to fluconazole 1

Proper Administration Technique

Critical for efficacy: The patient must swish the nystatin suspension thoroughly in the mouth for at least 2 minutes, ensuring contact with all affected areas, then swallow (do not spit out) to treat potential esophageal involvement 2

• Continue the full 7-14 day course even if symptoms improve earlier 2
• For denture-related candidiasis, denture disinfection must accompany antifungal therapy—this is strongly recommended and non-negotiable 3, 2

Special Populations and Considerations

Immunocompromised Patients

• Treatment duration may need extension beyond 14 days 3
• Systemic therapy (fluconazole) is more appropriate than topical nystatin for this population 2
• For HIV-infected patients with recurrent infections, antiretroviral therapy is strongly recommended alongside antifungal treatment to reduce recurrence rates 3, 2

Recurrent Infections

• Multiple courses of therapy or suppressive therapy are major risk factors for developing azole-refractory infection 1
• For chronic suppression when needed, fluconazole 100 mg three times weekly is recommended rather than continuous nystatin 2
• Fluconazole provides a longer disease-free interval before relapse (18% relapse at day 28) compared to nystatin (44% relapse) 4

Evidence Quality and Comparative Efficacy

The evidence consistently demonstrates nystatin's limitations:

• Clinical cure rates: Nystatin achieves only 32-54% cure rates compared to 100% with fluconazole in infants 2
• Mycological eradication: Fluconazole eradicates Candida from oral flora in 60% versus only 6% with nystatin 4
• Tolerability: Nystatin has suboptimal tolerability with poor taste and gastrointestinal adverse effects being most common 5
• Half of patients report inconvenience from nystatin medication compared to 23% with fluconazole 6

Common Pitfalls to Avoid

• Do not use nystatin as first-line for moderate-to-severe disease—fluconazole is superior 2, 4
• Do not rely on oropharyngeal fungal cultures—many individuals have asymptomatic colonization, and treatment frequently does not result in microbiological cure 1
• Do not forget denture disinfection when treating denture-related candidiasis—antifungal therapy alone will fail 3, 2
• If symptoms persist beyond the recommended treatment duration, reevaluate for resistant organisms or alternative diagnoses 3

Treatment Response Timeline

• Clinical response should be evident within 48-72 hours for most infections 3
• Mycological cure typically occurs within 4-7 days 3
• If no improvement by 72 hours, consider switching to systemic fluconazole 2, 4