Fluconazole (Diflucan) Treatment Regimens for Fungal Infections
Fluconazole dosing regimens vary based on the type of fungal infection, severity, and patient factors, with specific recommendations for each condition as outlined in clinical practice guidelines.
Candidiasis Treatment Regimens
Invasive Candidiasis/Candidemia
- For non-neutropenic adults: Fluconazole 800 mg (12 mg/kg) loading dose, then 400 mg (6 mg/kg) daily for candidemia without metastatic complications 1
- Treatment should continue for 2 weeks after documented clearance of Candida from bloodstream and resolution of symptoms 1
- For step-down therapy after initial treatment with other antifungals, fluconazole 400-800 mg (6-12 mg/kg) daily is recommended for susceptible isolates 1
Oropharyngeal Candidiasis
- Fluconazole 100-200 mg daily for 7-14 days 1
- For HIV-infected patients, higher doses may be needed for longer duration 2
Esophageal Candidiasis
- Fluconazole 200-400 mg daily for 14-21 days until clinical improvement is seen 1
- Can be used as step-down therapy after initial treatment with other antifungals in severe cases 1
Vulvovaginal Candidiasis
- Uncomplicated: Single 150 mg oral dose 3
- Complicated/severe: Two 150 mg doses given 3 days apart 4
- For recurrent vulvovaginal candidiasis: Initial control followed by fluconazole 150 mg weekly for 6 months 1
Urinary Tract Candida Infections
- Symptomatic cystitis: Fluconazole 200 mg (3 mg/kg) daily for 14 days 1
- Pyelonephritis: Fluconazole 200-400 mg (3-6 mg/kg) daily for 14 days 1
- For patients undergoing urologic procedures with asymptomatic candiduria: Fluconazole 200-400 mg (3-6 mg/kg) daily for several days before and after the procedure 1
Special Populations
Neonatal Candidiasis
- Fluconazole 12 mg/kg daily intravenous or oral as a reasonable alternative to amphotericin B in patients who have not been on fluconazole prophylaxis 1
- For prophylaxis in high-risk nurseries (>10% invasive candidiasis): Fluconazole 3-6 mg/kg twice weekly 1
CNS Candidiasis
- Fluconazole 400-800 mg (6-12 mg/kg) daily for patients unable to tolerate amphotericin B 1
- Continue therapy until all signs, symptoms, CSF and radiological abnormalities have resolved 1
- Can be used as step-down therapy after initial treatment with other antifungals 1
Other Fungal Infections
Cryptococcal Meningitis
- Initial treatment often includes amphotericin B with flucytosine, followed by fluconazole 400 mg daily for step-down therapy 2
- For maintenance therapy in AIDS patients: Fluconazole 200 mg daily until immune reconstitution 1
Chronic Disseminated Candidiasis
- Fluconazole 400 mg (6 mg/kg) daily until lesions have resolved (usually 3-6 months) 1
- Can be used as step-down therapy after initial treatment with lipid formulation amphotericin B 1
Important Considerations
- Adjust dosing in renal impairment: Reduce dose based on creatinine clearance 2
- Drug interactions: Fluconazole may interact with other medications metabolized by CYP450 enzymes 2
- Resistance concerns: Consider susceptibility testing for non-albicans Candida species, which may have reduced response to fluconazole 4
- Duration of therapy: Should be determined by clinical response and eradication of the infection 1
- Source control: For intra-abdominal candidiasis, appropriate drainage and/or debridement is essential in addition to antifungal therapy 1
Common Pitfalls
- Failing to give a loading dose for invasive infections can delay achieving therapeutic levels 1
- Not continuing therapy for sufficient duration after clinical improvement may lead to relapse 1
- Respiratory tract Candida isolation usually represents colonization and rarely requires antifungal therapy 1
- Using fluconazole for species with known resistance (e.g., some C. glabrata and C. krusei) 4
- Not considering drug interactions when prescribing fluconazole with other medications 2