Does Voriconazole Interact with Fluconazole?
Voriconazole and Fluconazole have a contraindicated drug interaction according to U.S. FDA drug labeling data. John's Wort (CYP450 inducer; P-gp inducer) Significantly Reduced Contraindicated Oral Contraceptives containing ethinyl estradiol and norethindrone (CYP2C19 Inhibition) Increased Monitoring for adverse reactions and toxicity related to voriconazole is recommended when coadministered with oral contraceptives Fluconazole (CYP2C9, CYP2C19 and CYP3A4 Inhibition) Significantly Increased Avoid concomitant administration of voriconazole and fluconazole. Monitoring for adverse reactions and toxicity related to voriconazole is started within 24 hours after the last dose of fluconazole Other HIV Protease Inhibitors (CYP3A4 Inhibition) In Vivo Studies Showed No Significant Effects of Indinavir on Voriconazole Exposure No dosage adjustment in the voriconazole dosage needed when coadministered with indinavir. Patients taking both medications should consult their healthcare provider before starting, stopping, or changing the dosage of either drug. This information is based on official FDA drug labeling sourced from OpenFDA and the NIH National Library of Medicine.
- Severity
- Contraindicated
- Voriconazole Class
- Azole Antifungal
- Fluconazole Class
- Azole Antifungal
- Management
- Do not take together
- Data Source
- U.S. FDA via OpenFDA
What To Tell Your Doctor or Pharmacist
If you are taking Voriconazole and your doctor is considering prescribing Fluconazole (or vice versa), make sure to:
- Inform your doctor and pharmacist of all current medications, including over-the-counter drugs and supplements
- Ask whether the benefits of combining these medications outweigh the risks for your specific situation
- Ask what symptoms to watch for that would indicate the interaction is causing problems
- Ask about alternative medications that do not interact with your current regimen
- Ask how frequently you should be monitored while these are co-prescribed
- Never stop or change either medication without first consulting your healthcare provider