What is the recommended dosage of fluconazole (antifungal medication) prior to penile prosthesis insertion?

Fluconazole Dosage for Penile Prosthesis Insertion

For patients undergoing penile prosthesis insertion, oral fluconazole should be administered at a dose of 400 mg (6 mg/kg) daily for several days before and after the procedure. 1

Rationale and Evidence

• Penile prosthesis insertion is considered a urologic procedure that puts patients at risk for fungal infections, particularly candidiasis 1
• The Infectious Diseases Society of America (IDSA) guidelines specifically recommend prophylactic antifungal therapy for patients undergoing urologic procedures 1
• This recommendation is based on the understanding that urologic manipulation increases the risk of fungal dissemination 1

Administration Protocol

• Timing: Start fluconazole several days before the procedure and continue for several days after 1
• Dosage: 400 mg (6 mg/kg) daily 1
• Route: Oral administration is preferred due to excellent bioavailability (>93%) 2

Alternative Options

• For patients with contraindications to fluconazole or suspected fluconazole-resistant organisms:
  • Amphotericin B deoxycholate at 0.3-0.6 mg/kg daily can be used for several days before and after the procedure 1
  • This alternative should be considered especially if there is concern for resistant Candida species such as C. glabrata or C. krusei 1

Special Considerations

• Renal function: For patients with impaired renal function, dose adjustment may be necessary 3
• Drug interactions: Monitor patients taking concomitant medications such as:
  • Coumarin anticoagulants (increased anticoagulant effect) 4
  • Oral hypoglycemics (increased hypoglycemic effect) 4
  • Cyclosporine (potential interaction at higher doses) 5

Monitoring

• Assess for clinical signs of fungal infection post-procedure 1
• Monitor liver function tests in patients receiving prolonged therapy 6
• Be vigilant for potential development of resistant Candida species, particularly with prolonged use 7

Pharmacokinetic Considerations

• Fluconazole has excellent tissue penetration and a long half-life (25-30 hours) 2, 4
• It achieves high concentrations in urine, making it particularly effective for urologic procedures 2
• The drug is primarily eliminated unchanged in urine (approximately 70% of dose) 4