Felodipine and Fluconazole: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Fluconazole
Felodipine
How we grade severity & evidence
Severity levels
- Contraindicated: These should generally not be used together.
- Major: Potentially serious — often needs a change or close monitoring.
- Moderate: Can be significant — usually manageable with monitoring.
- Minor: Usually limited clinical impact.
Evidence grades
- Established: Well documented — supported by controlled studies or strong clinical data.
- Probable: Good supporting evidence, though not definitively proven.
- Suspected: Some evidence suggests this interaction, but it is not well established.
- Possible: Limited or conflicting evidence; the interaction may occur.
- Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.
Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.
What happens
Increased felodipine exposure and toxicity (dizziness, hypotension, flushing, headache, peripheral edema)
Interaction Deep Dive
Concomitant administration of fluconazole with felodipine (a calcium channel antagonist metabolized by CYP3A4) may increase the exposure of felodipine. Frequent monitoring for adverse events is recommended1. Triazole antifungals (itraconazole, fluconazole) and imidazole antifungals (ketoconazole) inhibit hepatic isoenzyme CYP3A4, an enzyme involved in the metabolism of dihydropyridine calcium channel antagonists (NIFEdipine, niCARdipine, amLODIPine, isradipine, felodipine) 4. Literature reports have documented substantial peripheral edema and/or elevated calcium antagonist serum concentrations during concurrent use of itraconazole and felodipine, isradipine, or NIFEdipine 35.
Why it happens (mechanism)
Inhibition of CYP3A4-mediated metabolism of felodipine
Literature reports
2 reports — tap to read
a) A case report of a 68-year-old woman taking NIFEdipine and atenolol for hypertension was started on itraconazole for pedal onychomycosis reported ankle edema. She apparently had never had ankle edema before. The ankle edema appeared after two to three days of itraconazole and resolved two to three days after itraconazole was discontinued. The ankle edema reappeared with each subsequent course of itraconazole except the final course. NIFEdipine trough concentrations were obtained with the last course of therapy. Relative to the itraconazole therapy trough NIFEdipine trough concentrations were obtained on 4 days prior to and three days during therapy. The mean NIFEdipine trough concentration prior to therapy was 12.7 nanogram/mL (ng/mL; 36.7 nanomol/L) and 56.1 ng/mL (162 nanomol/L) during itraconazole therapy 2.
b) Peripheral edema and elevated serum felodipine levels were described in two patients receiving combined therapy with felodipine and itraconazole. Swelling of the lower extremities occurred in both cases within 3-7 days and resolved within 2-4 days following discontinuation of one of the agents. Re-challenge in one of the patients resulted in reoccurrence of the edema. In this patient, area under the felodipine plasma concentration-time curve (AUC) was found to be at least four times higher with itraconazole therapy 3.
Common questions
Can I take Felodipine and Fluconazole together?
Increased felodipine exposure and toxicity (dizziness, hypotension, flushing, headache, peripheral edema) Always confirm with your pharmacist or prescriber before making any change.
How serious is the Felodipine and Fluconazole interaction?
It is rated major. Potentially serious — often needs a change or close monitoring.
How quickly could this interaction happen?
The documented onset is "delayed". Effects tend to build up gradually over days to weeks.
How strong is the evidence for this interaction?
The evidence is graded "probable". Good supporting evidence, though not definitively proven.
From our Q&A
Real reader questions about these medications, each personally answered by our pharmacist:
Questions for your pharmacist
- Does my dose of Felodipine or Fluconazole need adjusting while I take them together?
- What symptoms should prompt me to call you or my prescriber right away?
- Does the timing of my doses matter for this combination?
- Is there a safer alternative to one of these medications for me?
References (5)
- Product Information: DIFLUCAN(R) oral tablets, suspension, fluconazole oral tablets, suspension. Roerig (per FDA), New York, NY, 2023. DailyMed
- Tailor S, Gupta A, Walker S, et al: Peripheral edema due to nifedipine-itraconazole interaction: a case report. Arch Dermatol 1996; 132:350-352. DOI
- Neuvonen PJ & Suhonen R: Itraconazole interacts with felodipine. J Am Acad Dermatol 1995; 33:134-135. PubMed
- Gibaldi M: Drug interactions: part I. Ann Pharmacother 1992; 26:709-713. PubMed
- Tailor S, Gupta A, Walker S, et al: Peripheral edema due to nifedipine-itraconazole interaction: a case report. Arch Dermatol 1996; 132:350-352. DOI
Keep reading about Fluconazole
Keep reading about Felodipine
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