From the Guidelines
Fluconazole should be administered at a dose of 400 mg (6 mg/kg) daily for patients with normal renal function, and dose adjustments are necessary for patients with impaired renal function, with a reduction to 50% of the standard dose for creatinine clearance of 21-50 mL/min and 25% for creatinine clearance ≤20 mL/min, as recommended by the Infectious Diseases Society of America 1. The dosing frequency of fluconazole is typically once daily, and it is essential to consider the patient's renal function when determining the dose. For patients with normal renal function, the standard dose is 400 mg daily 1. However, for patients with impaired renal function, the dose needs to be adjusted to prevent accumulation of the drug and potential toxicity.
- Key considerations for fluconazole dosing include:
- The drug's elimination is almost entirely renal, making dose adjustments crucial for patients with impaired renal function 1.
- Fluconazole achieves high urinary concentrations, making it effective for urinary tract infections, including uncomplicated candiduria 1.
- The medication is generally well-tolerated, but patients should be monitored for potential side effects, including elevated liver enzymes, and drug interactions should be considered 1. In clinical practice, fluconazole is a commonly used antifungal medication due to its efficacy, safety profile, and ease of administration. Its high oral bioavailability and penetration into various body fluids, including urine and cerebrospinal fluid, make it a preferred option for treating various fungal infections, including candidiasis 1.
From the FDA Drug Label
The recommended dosage of fluconazole tablets for suppression of relapse of cryptococcal meningitis in patients with AIDS is 200 mg once daily. Dosage In Patients With Impaired Renal Function: Fluconazole is cleared primarily by renal excretion as unchanged drug. In patients with impaired renal function who will receive multiple doses of fluconazole tablets, an initial loading dose of 50 mg to 400 mg should be given After the loading dose, the daily dose (according to indication) should be based on the following table: Creatinine Clearance (mL/min) Recommended Dose (%)
50 100 ≤50 (no dialysis) 50 Hemodialysis 100% after each hemodialysis
The recommended fluconazole dose and frequency for treating fungal infections, particularly uncomplicated candiduria, is not directly stated in the provided drug label. However, for patients with normal renal function, the label suggests doses ranging from 100 mg to 400 mg once daily for various fungal infections.
- For patients with impaired renal function, the dose should be adjusted based on creatinine clearance, with a recommended dose of 50% of the normal dose for patients with creatinine clearance ≤50 mL/min and 100% of the dose after each hemodialysis for patients on hemodialysis 2.
- The label does not provide specific dosing recommendations for uncomplicated candiduria.
- It is essential to note that the dosing recommendations may vary depending on the specific fungal infection being treated and the patient's renal function.
From the Research
Fluconazole Dose and Frequency
The recommended fluconazole dose and frequency for treating fungal infections, particularly uncomplicated candiduria, vary depending on the patient's renal function.
- For patients with normal renal function, a fluconazole dose of 200 mg loading dose followed by 100 mg/day for at least four days is recommended for the treatment of symptomatic candidal urinary tract infection (UTI) 3.
- For patients with impaired renal function, the dosage may need to be adjusted. A study found that amphotericin B bladder irrigations (ABBI) may be considered an alternative to fluconazole for the treatment of candiduria, especially in patients with renal dysfunction 4.
- In patients receiving continuous hemodiafiltration, a dosing regimen of 500-600 mg intravenously every 12 h is recommended to maintain effective plasma concentration 5.
Dosage Recommendations
The following dosage recommendations are based on the available evidence:
- Uncomplicated candiduria: 200 mg loading dose followed by 100 mg/day for at least four days 3
- Candiduria in patients with impaired renal function: consider alternative treatment with ABBI 4
- Patients receiving continuous hemodiafiltration: 500-600 mg intravenously every 12 h 5
- Systemic fungal infections: higher doses of 200-400 mg daily for long periods may be used 6
Special Considerations
- Fluconazole is poorly metabolized and mainly eliminated unchanged in the urine, with a half-life of 37.2 +/- 5.5h in patients with AIDS 6.
- The volume of distribution remains stable at 46.3 +/- 7.9L and is considered an 'invariant' parameter across species 6.
- Bioavailability exceeds 93% for tablets, suspension, and suppositories 6.