Section 15 · Monograph
Fluconazole
Reviewed Nov 2026FDA label
DiflucanTriazole antifungal
- Forms
- Tab: 50, 100, 150, 200mg | IV: 200, 400mg
- Dose
- Cryptococcal meningitis consolidation: 400-800mg/day x8 weeks, then 200mg/day maintenance (after amphotericin/flucytosine induction)
- MOA
- Inhibits fungal CYP51 (ergosterol synthesis)
Indications
- Vaginal, oropharyngeal and esophageal candidiasisFDA-labeled
- Cryptococcal meningitisFDA-labeled
Mechanism of Action
- Triazole that inhibits fungal cytochrome P450 14-alpha-demethylase (CYP51), blocking ergosterol synthesis; excellent CSF penetration
Full Dosing
Adult / usual
- Cryptococcal meningitis: induction with liposomal amphotericin B plus flucytosine; consolidation 400-800mg/day for 8 weeks, then maintenance 200mg/day for at least 1 year (until immune recovery)
- IV and oral dosing are equivalent
Renal
- Adjust for CrCl below 50mL/min
Contraindications
- Hypersensitivity to fluconazole or azoles
- Coadministration with terfenadine (multiple dosing), cisapride, pimozide, quinidine or other QT-prolonging CYP3A4 substrates
Drug Interactions
- CYP2C9/2C19/3A4 inhibition: raises phenytoin, carbamazepine, warfarin and many other drugs
- QT-prolonging agents including pimozide
- Rifampin lowers fluconazole levels
Adverse Effects
- Hepatotoxicity
- QT prolongation
- Rash and Stevens-Johnson syndrome
- Nausea, headache
Monitoring Parameters
- Liver enzymes
- ECG with QT-prolonging drugs
- Cryptococcal antigen and CSF cultures
Pregnancy & Lactation
- High-dose use in the first trimester has been associated with congenital malformations; avoid unless needed
- Present in milk at levels low enough to be acceptable