Itraconazole Dosage and Treatment Plan for Fungal Infections
The recommended dosage of itraconazole varies by infection type, with the standard regimen being 200 mg three times daily for 3 days (loading dose) followed by 200 mg once or twice daily for 6-12 months for most systemic fungal infections. 1
Dosing Recommendations by Infection Type
Blastomycosis and Other Systemic Fungal Infections
- For mild to moderate disease: Oral itraconazole 200 mg three times daily for 3 days, then 200 mg once or twice daily for 6-12 months 1
- For severe disease: Initial treatment with amphotericin B (3-5 mg/kg/day) for 1-2 weeks until improvement, followed by itraconazole 200 mg three times daily for 3 days, then 200 mg twice daily for 6-12 months 1
- For osteoarticular involvement: Total treatment duration of at least 12 months 1
Mucocutaneous Candidiasis
- Oropharyngeal candidiasis: Itraconazole 200 mg daily for 7-14 days 1
- Esophageal candidiasis: Itraconazole 200 mg daily for 14-21 days until clinical improvement 1
Dermatophyte Infections (Superficial)
Monitoring and Important Considerations
Therapeutic Drug Monitoring
- Serum levels of itraconazole should be determined after at least 2 weeks of therapy to ensure adequate drug exposure 1
- Target trough levels should be above 2.5 μg/ml for effective treatment 3
Dosage Adjustments
- Higher doses (up to 600 mg/day) have been used in severe infections with treatment failures, but with increased risk of side effects 3
- Dose reduction may lead to treatment failure if serum levels fall below therapeutic range 3
Administration Guidelines
- Oral capsules should be taken with food to enhance absorption 4
- Oral solution should be taken on an empty stomach to maximize absorption 4
- For patients unable to tolerate oral therapy, intravenous formulation is available 4
Special Populations and Situations
Immunocompromised Patients
- In HIV/AIDS patients or other immunosuppressed individuals: Consider longer treatment durations and monitor drug levels more frequently 1
- May be used for prophylaxis in high-risk immunocompromised patients 5, 4
Drug Interactions
- Significant potential for drug interactions through cytochrome P450 enzyme 3A4 system 6
- Avoid co-administration with medications metabolized by CYP3A4 when possible 6
- Be cautious with anticonvulsants, which may interact with itraconazole 1
Side Effects and Monitoring
- Monitor liver function tests as transient changes occur in 1-2% of patients 5
- Watch for hypokalemia, hypertension, and adrenal insufficiency, especially with higher doses 3
- Generally well-tolerated at standard doses up to 400 mg/day 6