Fluconazole Dosing for Fungal Infections

Introduction to Fluconazole Treatment

The American College of Microbiology recommends a loading dose of 800 mg (12 mg/kg) on day 1, followed by 400 mg (6 mg/kg) daily maintenance dosing for systemic candidiasis 1, 2

For systemic candidiasis, the maintenance dose is 400 mg (6 mg/kg) daily 1, 2, 4
The treatment duration for systemic candidiasis is 2 weeks after first negative blood culture and resolution of symptoms 1, 3
For candidemia without persistent fungemia or metastatic complications, treat for 2-3 weeks after neutropenia resolution and negative cultures 5, 6

The dose for CNS candidiasis is 400-800 mg (6-12 mg/kg) daily for patients unable to tolerate amphotericin B 5, 6, 2
Treatment should continue until all signs, symptoms, CSF abnormalities, and radiologic findings resolve 5, 6

For symptomatic cystitis, the dose is 200 mg (3 mg/kg) daily for 14 days 5, 6, 2, 4, 3
For pyelonephritis, the dose is 200-400 mg (3-6 mg/kg) daily for 14 days 5, 6, 2, 4, 3

Fluconazole has no activity against Candida krusei and variable activity against C. glabrata—confirm susceptibility before use 2, 4
For C. parapsilosis, fluconazole is appropriate; if echinocandin used initially, consider switching to fluconazole 6
For C. glabrata, use echinocandin or amphotericin B initially; only switch to fluconazole if susceptibility confirmed and patient clinically improved 6
For C. krusei, use echinocandin, amphotericin B, or voriconazole—fluconazole is not effective 6

Inadequate treatment duration can lead to relapse; continue until clinical and laboratory parameters indicate resolution 2
Resistance development is particularly problematic in patients with recurrent or chronic infections 3
Neutropenic patients require longer treatment duration (2 weeks after neutropenia resolution) 6