What is the recommended dose of itraconazole (antifungal medication) for children?

Itraconazole Dosing in Children

The recommended dose of itraconazole for children is 5 mg/kg/day given in two divided doses (2.5 mg/kg twice daily) for most indications, with treatment doses increased to 10 mg/kg/day in two divided doses for systemic fungal infections. 1

Standard Dosing Recommendations

• Prophylaxis: 2.5 mg/kg twice daily (5 mg/kg/day) 1
• Oropharyngeal candidiasis: 2.5 mg/kg twice daily 1
• Esophageal candidiasis: 2.5 mg/kg twice daily (5 mg/kg/day), with a loading dose of 5 mg/kg twice daily (10 mg/kg/day) on day 1 1
• Systemic fungal infections: 10 mg/kg/day in two divided doses 1, 2
• Superficial fungal infections: 5 mg/kg/day for shorter duration therapy 2, 3

Age-Based Dosing Considerations

Research evidence suggests that younger children may require higher doses:

• Children ≤12 years often require higher doses than the standard recommendation, with a median of 6.2 mg/kg/day needed to achieve therapeutic levels 4
• 71.4% of children ≤12 years required doses above the recommended 5 mg/kg/day to reach target concentrations 4
• Children >12 years typically require lower doses (median 3.9 mg/kg/day) 4

Formulation Preferences

• Oral solution (cyclodextrin) is the preferred formulation for children 1
• Capsules and oral solution should not be used interchangeably 1
• Capsules are generally ineffective for treating esophageal disease 1

Therapeutic Drug Monitoring (TDM)

• TDM is strongly recommended for all children receiving itraconazole 1
• Target trough concentration: ≥0.5 mg/L 1, 4
• Samples should be taken at steady state (typically after 5-7 days of therapy) 4
• Dose adjustments should be made when levels are subtherapeutic 4

Common Pitfalls and Caveats

1. Inadequate monitoring: Studies show poor compliance with TDM guidelines, with only 28.6% of subtherapeutic levels resulting in appropriate dose adjustments 4

2. Underdosing in younger children: Standard dosing often results in subtherapeutic levels in children under 12 years 4

3. Drug interactions: Itraconazole interacts with several medications commonly used in pediatric patients, particularly vincristine and irinotecan, which may increase the risk of adverse effects 5

4. Formulation errors: Using capsules instead of oral solution can result in treatment failure, especially for esophageal disease 1

5. Adverse effects: Most common include gastrointestinal symptoms (15.2%) and hepatotoxicity (6.5%) 4, 5

Itraconazole has demonstrated good safety and efficacy in pediatric populations when dosed appropriately and monitored carefully, with a favorable risk-benefit profile for both superficial and systemic fungal infections 2, 3.