Fluconazole Dosing for Fungal Infections
The recommended dosing for fluconazole varies by type of fungal infection, with standard dosing ranging from 100-400 mg daily depending on infection site and severity.
Oropharyngeal Candidiasis
- For oropharyngeal candidiasis, the recommended dose is 200 mg on the first day, followed by 100 mg once daily for 7-14 days 1
- Treatment should be continued for at least 2 weeks to decrease the likelihood of relapse 2
- For children, the dose is 3 mg/kg daily (equivalent to 100 mg in adults) 1
Esophageal Candidiasis
- For esophageal candidiasis, the recommended dose is 200 mg on the first day, followed by 100 mg once daily 1, 2
- Treatment should continue for a minimum of three weeks and for at least two weeks following resolution of symptoms 2
- Doses up to 400 mg daily may be used in severe cases based on clinical response 1, 2
Vaginal Candidiasis
- For vaginal candidiasis, a single 150 mg oral dose is recommended 2
- This single-dose regimen provides a clinical cure rate of approximately 84% 3
Systemic Candida Infections
- For candidemia and disseminated candidiasis, the recommended dose is 400 mg (6 mg/kg) daily 1
- Optimal duration is not firmly established but should continue for 2 weeks after blood cultures become negative and symptoms resolve 1
- Central venous catheter removal is strongly recommended in cases of candidemia 1
Urinary Tract Infections
- For symptomatic cystitis, fluconazole 200 mg (3 mg/kg) daily for 14 days is recommended 4, 1
- For pyelonephritis, fluconazole 200-400 mg (3-6 mg/kg) daily for 14 days is recommended 4, 1
- For patients undergoing urologic procedures with asymptomatic candiduria, prophylactic fluconazole is recommended before and after the procedure 4
Cryptococcal Infections
- For cryptococcal meningitis, the recommended dose is 400 mg on the first day, followed by 200 mg once daily 2
- Treatment should continue for 10-12 weeks after cerebrospinal fluid becomes culture negative 2
- For suppression of relapse in AIDS patients, 200 mg once daily is recommended 2
Prophylaxis in Immunocompromised Patients
- For prevention of candidiasis in bone marrow transplant patients, 400 mg once daily is recommended 2
- Prophylaxis should start several days before anticipated severe granulocytopenia and continue for 7 days after neutrophil count rises above 1000 cells/mm³ 2
Special Considerations
- Fluconazole has excellent bioavailability (>93%) with oral administration, making oral and intravenous doses equivalent 2, 3
- No dosage adjustment is needed when switching between oral and intravenous routes 2
- Food intake and hypochlorhydria do not affect absorption of fluconazole 3
Common Pitfalls and Caveats
- Fluconazole resistance can develop, particularly in patients with recurrent or chronic infections 1
- For fluconazole-resistant Candida species (particularly C. glabrata and C. krusei), alternative antifungal agents should be used 4, 1
- Growth of Candida from respiratory secretions usually indicates colonization rather than infection and rarely requires antifungal therapy 1
- Maximum recommended daily dose is 1600 mg to avoid neurological toxicity 3
- An inadequate period of treatment may lead to recurrence of active infection 2