Nystatin Dosing Recommendations
The recommended dosing for nystatin varies by formulation and patient population, with oral suspension dosing being 400,000 to 600,000 units four times daily for adults and children, and 200,000 units four times daily for infants. 1
Oral Suspension Dosing
Adults and Children
- 4-6 mL (400,000-600,000 units) four times daily 1
- One-half of dose should be placed in each side of mouth
- Solution should be retained in the mouth as long as possible before swallowing
- Continue treatment for at least 48 hours after symptoms resolve and cultures demonstrate eradication of Candida albicans 1
Infants
- 2 mL (200,000 units) four times daily 1
- Use dropper to place one-half of dose in each side of mouth
- Avoid feeding for 5-10 minutes after administration
- For premature and low birth weight infants: 1 mL (100,000 units) four times daily is effective 1
Neonatal Prophylaxis
- 100,000 units 3 times daily for 6 weeks is recommended as an alternative to fluconazole in neonates with birth weights <1500g when fluconazole availability or resistance is a concern 2
Other Formulations and Indications
Oropharyngeal Candidiasis
- Nystatin suspension: 200,000-400,000 units four times daily 2
- Treatment duration: 7-14 days (1-7 days in children) for uncomplicated disease 2
Vulvovaginal Candidiasis
- Nystatin intravaginal suppositories: 100,000 units daily for 14 days (particularly for C. glabrata infections) 3
Clinical Considerations
Efficacy Factors
- Nystatin pastilles have been shown to be more effective than suspension due to longer persistence of antifungal activity in the oral cavity (detectable for at least 5 hours vs. rapid elimination with suspension) 4
- The concentration of nystatin needed to kill clinical isolates of Candida albicans varies (1.875 to 30 U/ml), with killing time ranging from 120 to 300 minutes 4
Special Applications
- Topical nystatin powder (6,000 units/g) has been used successfully for angioinvasive fungal infections in severe burns when other topical and systemic agents have failed 5
Prophylaxis Considerations
- While nystatin (6,000 IU/day) has been used for prophylaxis in neutropenic patients, it was less effective than fluconazole (200 mg/day) in preventing fungal infections in patients with leukemia 6
- Nystatin prophylaxis may alter colonization patterns but has not consistently prevented disseminated fungal infection 7
Administration Tips
- For oral suspension, instruct patients to swish the medication throughout the mouth before swallowing or spitting
- Administer after meals for better contact time with oral mucosa
- Avoid eating or drinking for at least 30 minutes after administration
Remember that nystatin is a topical antifungal with minimal systemic absorption, making it safe for use in most patient populations but limiting its effectiveness to the surfaces it directly contacts.