Fluconazole

C. diff Risk

Low

Oral Bioavailability

Excellent

Approximate Cost

IV-$15/d PO-$3/d

Spectrum Of Activity

Dosing

Loading: 6 mg/kg/dose PO/IV
Maintenance: 3 mg/kg/dose PO/IV q24h
Maximum: 200 mg/dose

Loading: 6 mg/kg/dose PO/IV
Maintenance: 3-12 mg/kg/dose PO/IV q24h
Maximum: 400 mg/dose

6-12 mg/kg/dose PO/IV q24h
Maximum: 800 mg/dose

Loading: 12 mg/kg/dose PO/IV
Maintenance: 6-12 mg/kg/dose PO/IV q24h
Maximum: 800 mg/dose

5 mg/kg/dose IV/PO q24h
Maximum: 400 mg/dose

Post natal age less than or equal to 14 daysPost natal age greater than 14 days12 mg/kg/dose IV/PO q48h12 mg/kg/dose IV/PO q24h

Post natal age less than or equal to 7 daysPost natal age greater than 7 days12 mg/kg/dose IV/PO q48h12 mg/kg/dose IV/PO q24h

Consider prophylaxis only in extremely low birth weight infants (birthweight less than 1 kg) Starting on day 3 of life:
3 mg/kg/dose IV/PO q72h and continue until 6 weeks of age or until IV access no longer required.

Post natal age less than or equal to 14 daysPost natal age greater than 14 days6 mg/kg/dose IV/PO on day 1, followed by 3 to 6 mg/kg/dose IV/PO q72h ; change to q24h once beyond the first 2 weeks of life 6 mg/kg/dose IV/PO on day 1, followed by 3 to 6 mg/kg/dose IV/PO q24h

6 mg/kg/dose IV/PO on day 1, followed by 3 to 6 mg/kg/dose IV/PO q24h

Renally cleared, requires dosage adjustment with changes in renal function. Consult a pharmacist for renal dosing

Daily dose of fluconazole is the same for oral and IV administration unless otherwise specified

General Information

Common Usage

  • Candida infections both mucocutaneous and invasive - i.e. Candidemia

  • Cryptococcus and Coccidioides infections

  • Antifungal prophylaxis in immunocompromised

Drug Monitoring

Consider QTc monitoring if concomitant drugs affecting the interval or elevated baseline measurement

Adverse Effects

  • QTc prolongation

  • Hepatic enzyme abnormalities

  • Rash

  • GI upset

Major Interactions

  • Many via CYP450 - suggest review interactions with pharmacist.

  • Risk when combining with other QTc prolonging medications

Oral Liquids

Concentration: 10 mg/mL

Taste: palatable

Not all strengths of oral liquids are listed nor are available on IWK formulary

Tablet/Capsule Strengths

  • 50 mg tablet

  • 100 mg tablet

  • Tablets and capsules are preferred especially over an unpleasant tasting liquid.

  • Not all strengths of oral tablets/capsules are listed and they are not all available on the IWK formulary.

Pharmacology

Antimicrobial class: Triazole antifungal

Average serum half life:

  • Premature neonates: 47-73.6 hours.

  • Pediatrics (9 months to 15 years): oral 19.5-25 hours

  • 5- 15 years: IV 15-18 hours

  • Adults: Normal renal function: ~30 hours

Route of Elimination:

  • 80% unchanged in urine; 11% metabolites in urine.