Is fluconazole (FLU) 100mg per day for 7 days an effective treatment for yeast in urine?

Treatment of Yeast in Urine with Fluconazole

For fluconazole-susceptible Candida species causing urinary tract infection, oral fluconazole 200 mg (3 mg/kg) daily for 2 weeks is the recommended treatment, not 100 mg for 7 days. 1

Dosing Recommendations Based on Evidence

For Candida Cystitis (Lower UTI):

• First-line treatment:
  • Fluconazole 200 mg (3 mg/kg) daily for 2 weeks 1
  • Consider a 200 mg loading dose followed by 100 mg daily for at least 4 days if shorter duration is desired 2
• Important adjunctive measures:
  • Remove indwelling bladder catheter if present 1

For Candida Pyelonephritis (Upper UTI):

• Fluconazole 200-400 mg (3-6 mg/kg) daily for 2 weeks 1
• Address any urinary tract obstruction 1
• Consider removal/replacement of nephrostomy tubes or stents 1

Species-Specific Considerations

For non-albicans Candida species:

• C. glabrata (fluconazole-resistant):
  • Amphotericin B deoxycholate 0.3-0.6 mg/kg daily for 1-7 days OR
  • Oral flucytosine 25 mg/kg 4 times daily for 7-10 days 1
• C. krusei (intrinsically fluconazole-resistant):
  • Amphotericin B deoxycholate 0.3-0.6 mg/kg daily for 1-7 days 1

Clinical Pearls and Pitfalls

1. Pitfall: Inadequate dosing

   • 100 mg for 7 days is insufficient for treating urinary candidiasis
   • The FDA label indicates fluconazole is effective for Candida urinary tract infections but doesn't specify dosing 3
   • The IDSA guidelines clearly recommend 200 mg daily for 2 weeks 1

2. Pitfall: Failure to identify the Candida species

   • Specimens for fungal culture should be obtained prior to therapy 3
   • Many non-albicans species have high fluconazole MICs 4

3. Pitfall: Missing underlying factors

   • Failure to remove indwelling catheters when possible
   • Failure to address urinary tract obstruction
   • Not considering nephrostomy tubes or stents that may need replacement 1

4. Pharmacokinetic considerations:

   • Fluconazole concentrates in urine (60% of dose recovered unchanged in urine) 5
   • Long half-life (31-37 hours) allows for effective treatment 5

Special Populations

1. Patients undergoing urologic procedures:

   • Higher dose: Fluconazole 400 mg (6 mg/kg) daily for several days before and after the procedure 1

2. Asymptomatic candiduria:

   • Treatment generally not recommended unless patient is at high risk for dissemination:
     • Neutropenic patients
     • Very low birth-weight infants (<1500g)
     • Patients undergoing urologic manipulation 1

Monitoring and Follow-up

• Clinical response should be evident within days of starting therapy
• Follow-up urine cultures may be necessary to confirm eradication
• For recurrent infections, consider underlying structural abnormalities or immunosuppression

Fluconazole remains an effective treatment for susceptible Candida species in the urinary tract, but proper dosing (200 mg daily for 2 weeks) and identification of the causative species are essential for successful treatment.