Budesonide and Ketoconazole: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Ketoconazole
Budesonide
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 budesonide exposure
Interaction Deep Dive
Avoid use of budesonide delayed-release capsules with ketoconazole, a strong CYP3A4 inhibitor, as the exposure of budesonide may be increased1. Use caution while considering the coadministration of budesonide with ketoconazole 2534. Upon coadministration, monitor patients closely for signs or symptoms of increased or prolonged effects or side effects of budesonide, and reduce budesonide dosage as deemed necessary 5.
Why it happens (mechanism)
Inhibition of CYP3A4-mediated metabolism of budesonide
Literature reports
2 reports — tap to read
a) In an open, nonrandomized, cross-over study, coadministration of budesonide and ketoconazole resulted in 8-fold the AUC of budesonide, compared to budesonide alone. Six healthy subjects were given budesonide 10 mg as a single dose, either alone or concomitantly with the last ketoconazole dose of 3 days treatment with ketoconazole 100 mg twice daily 1.
b) A randomized, open crossover study involving eight healthy volunteers demonstrated the effect of ketoconazole on the elimination of budesonide. In period 1, a single dose of budesonide 3 mg was given in the morning without ketoconazole pretreatment. In the second period, ketoconazole was administered once daily in the morning on four consecutive days. Budesonide 3 mg was administered with ketoconazole on the fourth day. In period three, ketoconazole was administered once daily in the evening for four consecutive days. On the fourth day, budesonide was administered twelve hours before the last dose of ketoconazole. A significant increase in plasma concentrations of budesonide was observed during morning and evening treatment with ketoconazole. The mean Cmax of budesonide was increased by about 7.7 times and the mean AUC was increased by about 6.8 times when ketoconazole was administered with budesonide. The increase in the plasma concentration of budesonide was smaller when ketoconazole was administered twelve hours before budesonide. The mean Cmax of budesonide was increased by approximately 3.6 times and the mean AUC was increased by about 4 times 6.
Common questions
Can I take Budesonide and Ketoconazole together?
Increased budesonide exposure Always confirm with your pharmacist or prescriber before making any change.
How serious is the Budesonide and Ketoconazole interaction?
It is rated major. Potentially serious — often needs a change or close monitoring.
How quickly could this interaction happen?
The documented onset is "rapid". Effects can appear quickly, often within about 24 hours of combining the drugs.
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 Budesonide or Ketoconazole 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)
- Product Information: TARPEYO(TM) oral delayed-release capsules, budesonide oral delayed-release capsules. Calliditas Therapeutics AB (per FDA), Stockholm, Sweden, 2021. DailyMed
- Product Information: AIRSUPRA(TM) oral inhalation aerosol, albuterol budesonide oral inhalation aerosol. AstraZeneca Pharmaceuticals LP (per FDA), Wilmington, DE, 2023. DailyMed
- Product Information: SYMBICORT AEROSPHERE® oral inhalation aerosol, budesonide formoterol fumarate oral inhalation aerosol. AstraZeneca Pharmaceuticals LP, Wilmington, DE, 2026.
- Product Information: BREZTRI AEROSPHERE® inhalation aerosol, budesonide, glycopyrrolate, formoterol fumarate inhalation aerosol. AstraZeneca Pharmaceuticals LP, Wilmington, DE, 2026. DailyMed
- Product Information: Ketoconazole oral tablet, ketoconazole oral tablet. Taro Pharmaceuticals U.S.A. Inc. (per DailyMed), Hawthorne, NY, 2024. DailyMed
- Seidegard J: Reduction of the inhibitory effect of ketoconazole on budesonide pharmacokinetics by separation of their time of administration. Clin Pharmacol Ther 2000; 67:13-17. PubMed
Keep reading about Ketoconazole
Keep reading about Budesonide
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