Antifungal Medication Dosing and Duration for Fungal Infections
Candidiasis Treatment
For candidiasis treatment, fluconazole is typically administered at a loading dose of 800 mg (12 mg/kg) on day 1, followed by 400 mg (6 mg/kg) daily for 2 weeks after documented clearance of Candida from the bloodstream and resolution of symptoms. 1
Specific Candidiasis Infections:
- Uncomplicated vulvovaginal candidiasis: Fluconazole 150 mg as a single oral dose 2
- Severe acute vulvovaginal candidiasis: Fluconazole 150 mg every 72 hours for 2-3 doses total 2
- Recurrent vulvovaginal candidiasis: Initial induction with 10-14 days of topical agent or oral fluconazole, followed by maintenance therapy with fluconazole 150 mg weekly for 6 months 2
- Oropharyngeal candidiasis:
- Esophageal candidiasis: Fluconazole 200-400 mg daily for 14-21 days 1
- Urinary tract candidiasis: Fluconazole 200 mg daily for 2 weeks 2
- Pyelonephritis: Fluconazole 200-400 mg (3-6 mg/kg) daily for 14 days 1, 2
- Candida endophthalmitis: Treatment for at least 4-6 weeks, determined by repeated examinations to verify resolution 1
- CNS candidiasis: Fluconazole 400-800 mg (6-12 mg/kg) daily until all signs, symptoms, CSF abnormalities, and radiological abnormalities have resolved 1
Aspergillosis Treatment
For invasive aspergillosis, voriconazole is administered at a loading dose of 400 mg (6 mg/kg) every 12 hours for two doses on day 1, followed by 200-300 mg (3-4 mg/kg) twice daily for a minimum of 6-12 weeks, with treatment continuing until resolution or stabilization of all clinical and radiographic manifestations. 1
Alternative treatments for aspergillosis:
- Liposomal amphotericin B (L-AmB): 3-5 mg/kg IV daily 1
- Amphotericin B deoxycholate (AmB-d): 1.0-1.5 mg/kg IV daily 1
- Echinocandins (caspofungin: 70 mg loading dose, then 50 mg daily; micafungin: 100-150 mg daily; anidulafungin: 200 mg loading dose, then 100 mg daily) 1
Cryptococcosis Treatment
For cryptococcal meningitis, liposomal AmB 5 mg/kg daily with or without oral flucytosine 25 mg/kg 4 times daily is recommended for induction therapy, followed by fluconazole 400-800 mg (6-12 mg/kg) daily for step-down therapy, with total treatment duration of 6-18 months. 1
- Pulmonary cryptococcosis: Treatment for 6-12 months in immunocompetent patients 1
- Pulmonary cryptococcoma: Fluconazole 200-400 mg/day in immunocompetent patients with positive serum antigen 1
Important Considerations
Duration of Therapy:
- Candidemia: 2 weeks after documented clearance of Candida from the bloodstream and resolution of symptoms 1
- Invasive aspergillosis: Until resolution or stabilization of all clinical and radiographic manifestations 1
- Cryptococcal meningitis: 6-18 months, depending on clinical response 1
Dosage Adjustments:
- Renal impairment requires dose adjustment for fluconazole 3
- For patients on CAPD with fungal peritonitis, fluconazole 50 mg intraperitoneally or 100 mg orally is recommended 3
Treatment Efficacy:
- Fluconazole shows 53-90% success rates in systemic Candida infections 3, 4
- For Aspergillus infections, voriconazole doses of 300-600 mg may be needed to maximize efficacy (51-66.7% net benefit) depending on patient factors 5
Common Pitfalls:
- Fluconazole has limited activity against Aspergillus species; voriconazole or other agents should be used instead 6, 7
- Addressing underlying factors (e.g., disinfecting dentures in denture-related candidiasis) is crucial to prevent treatment failure 2
- Drug interactions, particularly between voriconazole and anticonvulsants, must be monitored 1
- Therapeutic drug monitoring is important for voriconazole to ensure adequate concentrations while minimizing toxicity 5