From the FDA Drug Label
USUAL DOSAGE: Apply to affected area 2 or 3 times daily. The dosing for nystatin in the treatment of diaper dermatitis is to apply to the affected area 2 or 3 times daily 1.
From the Research
For diaper rash, apply nystatin cream or ointment to the affected area 3-4 times daily after diaper changes, using a thin layer covering the entire rash, as this regimen has been shown to be effective in treating diaper dermatitis caused by Candida yeast 2. The typical formulation is 100,000 units/gram, which is the standard concentration for over-the-counter nystatin products 3. When using nystatin, it is essential to maintain good diaper hygiene, including frequent diaper changes and allowing air exposure to the affected area, to promote healing and prevent the growth of bacteria and yeast 4. Additionally, gently cleansing the area with warm water and patting it dry before applying nystatin can help prevent further irritation and infection. It is also crucial to wash hands before and after application to prevent the spread of infection. If the rash does not improve after a week of treatment, it is recommended to consult a pediatrician, as a bacterial infection may be present, requiring alternative treatment 2. Recent studies have also explored the use of topical skin barrier repair cosmetic products, such as zinc gluconate-taurine/zinc oxide and panthenol/glycerin/Butyrospermum parkii butter barrier cream, which have shown promise in treating mild to moderate diaper dermatitis 5. However, nystatin remains a widely used and effective treatment for diaper rash caused by Candida yeast, and its use should be prioritized in cases where a fungal infection is suspected.