Fluconazole Adverse Effects and Interactions

Known Adverse Effects

• The Centers for Disease Control and Prevention recommends monitoring for gastrointestinal effects, such as nausea and vomiting, which are the most common adverse effects of fluconazole 1, 2, 3
• The Centers for Disease Control and Prevention notes that asymptomatic transaminase elevations occur in 1-13% of patients taking fluconazole, with rare cases of hepatitis 1, 2, 3
• The National Comprehensive Cancer Network guidelines state that fluconazole can cause dermatologic reactions, including skin rash, pruritus, and alopecia, as well as rare cases of Stevens-Johnson syndrome 1, 2, 3
• The National Comprehensive Cancer Network recommends monitoring for cardiac effects, including QTc prolongation, when fluconazole is combined with other QT-prolonging drugs 4, 5, 6
• The Centers for Disease Control and Prevention reports that fluconazole can cause rare hematologic effects, including thrombocytopenia and leukopenia, more commonly associated with itraconazole than fluconazole 1, 2

Important Caveat: Drug Interactions

• The National Comprehensive Cancer Network guidelines warn that fluconazole can indirectly contribute to metabolic acidosis through drug-drug interactions, particularly by inhibiting cytochrome P450 enzymes 1, 2, 4, 5, 6

Renal Considerations

• The American Academy of Family Physicians recommends dose adjustment of fluconazole when creatinine clearance is <50 mL/min 7, 8

Clinical Monitoring

• The Praxis Medical Insights guideline recommends monitoring liver function, with baseline and periodic monitoring (at 2 weeks, 4 weeks, then every 3 months), particularly with prolonged fluconazole therapy 9