What are the dosing recommendations for Diflucan (fluconazole) for various fungal infections?

Fluconazole (Diflucan) Dosing Recommendations for Fungal Infections

Fluconazole dosing should be tailored to the specific fungal infection type, with 100-200 mg daily for mucocutaneous infections, 200-400 mg daily for invasive candidiasis, and 400-800 mg daily for CNS infections, with treatment duration ranging from 1-2 weeks for superficial infections to several months for systemic disease.

Candidiasis Dosing Guidelines

Mucocutaneous Candidiasis

• Oropharyngeal candidiasis:

  • 100-200 mg daily for 7-14 days 1
  • Continue for at least 48 hours after symptom resolution 2
  • For HIV/immunocompromised patients: may require longer treatment duration

• Esophageal candidiasis:

  • 200-400 mg daily for 14-21 days 1, 2
  • Treatment should continue until clinical improvement is seen 1

• Vulvovaginal candidiasis:

  • 150 mg single dose for uncomplicated cases 1
  • For recurrent vulvovaginal candidiasis: 150 mg weekly for 6 months after initial control 1

Invasive Candidiasis

• Candidemia/Systemic candidiasis:

  • Loading dose: 800 mg (12 mg/kg)
  • Maintenance: 400 mg (6 mg/kg) daily 1
  • Duration: At least 2 weeks after documented clearance from bloodstream and resolution of symptoms 2

• Urinary tract infections:

  • Symptomatic cystitis: 200 mg (3 mg/kg) daily for 14 days 1
  • Pyelonephritis: 200-400 mg (3-6 mg/kg) daily for 14 days 1

• Chronic disseminated candidiasis:

  • 400 mg (6 mg/kg) daily 1
  • Continue until lesions have resolved (usually 3-6 months) 1

Special Situations

• CNS candidiasis:

  • 400-800 mg (6-12 mg/kg) daily 1
  • For patients unable to tolerate amphotericin B
  • Continue until all signs, symptoms, CSF abnormalities, and radiologic abnormalities have resolved 1

• Candida endophthalmitis:

  • 400-800 mg (6-12 mg/kg) daily 1
  • Duration: At least 4-6 weeks, determined by repeated examinations 1

• Candida osteoarticular infections:

  • 400 mg (6 mg/kg) daily for 6-12 months 1
  • For septic arthritis: 400 mg (6 mg/kg) daily for at least 6 weeks 1

Pediatric Dosing

• Neonates (0-14 days):

  • 12 mg/kg daily, administered every 72 hours 1, 3

• Neonates (2-4 weeks):

  • 12 mg/kg daily, administered every 48 hours 3

• Infants >4 weeks:

  • 6-12 mg/kg daily 3

Dosing in Special Populations

• Renal impairment:

  • Creatinine clearance <50 mL/min: Reduce dose by 50% 2
  • ESRD patients: Consider alternative agents or adjusted dosing 2

• Prophylaxis in immunocompromised patients:

  • 100-400 mg daily 4
  • For recurrent esophageal candidiasis: 100-200 mg three times weekly 2

Clinical Pearls

1. Monitoring:

   • Assess clinical response within 3-5 days of treatment initiation
   • Monitor liver function tests if treatment extends beyond 7-10 days 2

2. Treatment failure considerations:

   • If no improvement after 7 days, consider:
     • Alternative diagnoses
     • Resistant Candida species
     • Need for longer treatment duration
     • Alternative antifungal agents 2

3. Maximum daily dose:

   • Total maximum daily dose of 1600 mg is recommended to avoid neurological toxicity 4

4. Pharmacokinetic considerations:

   • Excellent bioavailability (>93%) 4
   • Half-life approximately 30-37 hours 4
   • Primarily eliminated unchanged in urine (60%) 4
   • Food intake does not affect absorption 4

5. Efficacy rates:

   • Clinical cure rates range from 84-90% for mucocutaneous infections 4
   • Overall clinical efficacy rate of approximately 50-55% for systemic fungal infections in patients with hematological disorders 5, 6

Remember that treatment duration should be individualized based on the severity of infection, patient response, and immune status, with longer durations typically needed for immunocompromised patients.