Felodipine and Itraconazole: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Itraconazole
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 potential cardiotoxicity
Interaction Deep Dive
Concomitant use of felodipine and itraconazole, as well as use for 2 up to weeks after itraconazole discontinuation is contraindicated. Coadministration may lead to significantly increased felodipine exposure34, and may increase the risk of cardiac adverse events, including low blood pressure and increased heart rate. When these agents were coadministered, there were significant increases in AUC, Cmax, and t(1/2) of felodipine 5.
Why it happens (mechanism)
Inhibition of CYP3A4-mediated felodipine metabolism; additive negative inotropic effects
Literature reports
4 reports — tap to read
a) Felodipine coadministered with itraconazole has resulted in an approximately 8-fold increase in the AUC, more than a 6-fold increase in the Cmax, and a 2-fold prolongation in the half-life of felodipine 5.
b) 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 2 to 3 days of itraconazole therapy and resolved 2 to 3 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 concentrations were obtained on 4 days prior to and 3 days during therapy. The mean NIFEdipine trough concentration prior to therapy was 12.7 nanograms (ng)/mL and 56.1 ng/mL during itraconazole therapy 2.
c) Peripheral edema and elevated serum felodipine levels were described in 2 patients receiving combined therapy with felodipine and itraconazole. Swelling of the lower extremities occurred in both cases within 3 to 7 days and resolved within 2 to 4 days following discontinuation of one of the agents. Rechallenge in one of the patients resulted in reoccurrence of the edema. In this patient, felodipine AUC was found to be at least 4 times higher with itraconazole therapy 1.
d) In a controlled study of nine healthy volunteers, the pharmacokinetic effects of concurrent itraconazole and felodipine were examined. Subjects received itraconazole 200 mg or placebo for 4 days, followed by a single 5-mg dose of oral felodipine in a randomized, crossover design. There was a 4-week washout period between study phases. Blood samples were taken intermittently throughout the study to determine plasma concentrations of felodipine and itraconazole; blood pressure and heart rate measurements were also taken. During coadministration with itraconazole, mean felodipine maximum concentrations increased approximately 8-fold, from 1.2 +/- 0.1 nanograms (ng)/mL to 9.3 +/- 1.3 ng/mL. The felodipine AUC from 0 to 32 hours and the felodipine AUC from 0 hours to infinity were both significantly increased by 5-fold and 6-fold, respectively. The average half-life of felodipine was also increased from 15 +/- 3.5 hours to 25.7 +/- 4.6 hours during coadministration with itraconazole. Felodipine Tmax was unaffected by itraconazole. Pharmacodynamic effects of felodipine on blood pressure and heart rate were significantly greater during itraconazole coadministration compared to placebo 6.
Common questions
Can I take Felodipine and Itraconazole together?
Increased felodipine exposure and potential cardiotoxicity Always confirm with your pharmacist or prescriber before making any change.
How serious is the Felodipine and Itraconazole interaction?
It is rated contraindicated. These should generally not be used together.
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 "established". Well documented — supported by controlled studies or strong clinical data.
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 Itraconazole 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 (6)
- Neuvonen PJ & Suhonen R: Itraconazole interacts with felodipine. J Am Acad Dermatol 1995; 33:134-135. 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
- Product Information: SPORANOX(R) oral capsules, itraconazole oral capsules. Janssen Pharmaceuticals Inc (per FDA), Titusville, NJ, 2024. DailyMed
- Product Information: SPORANOX(R) oral solution, itraconazole oral solution. Janssen Pharmaceuticals Inc (per FDA), Titusville, NJ, 2024. DailyMed
- Product Information: PLENDIL(R) oral extended-release tablets, felodipine oral extended-release tablets. AstraZeneca LP (per FDA), Wilmington, DE, 2012. DailyMed
- Jalava K, Olkkola KT, & Neuvonen PJ: Itraconazole greatly increases plasma concentrations and effects of felodipine. Clin Pharmacol Ther 1997; 61:410-415. PubMed
Keep reading about Itraconazole
Keep reading about Felodipine
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