Dutasteride and Itraconazole: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Itraconazole
Dutasteride
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 dutasteride exposure and an increased risk of dutasteride-related adverse effects
Interaction Deep Dive
Concomitant use of itraconazole with dutasteride may increase the concentrations of dutasteride resulting in an increased risk of dutasteride-related adverse reactions. Monitor for adverse reactions of dutasteride. Dutasteride dose reduction may be necessary1.
Why it happens (mechanism)
Unknown
Common questions
Can I take Dutasteride and Itraconazole together?
Increased dutasteride exposure and an increased risk of dutasteride-related adverse effects Always confirm with your pharmacist or prescriber before making any change.
How serious is the Dutasteride and Itraconazole interaction?
It is rated major. Potentially serious — often needs a change or close monitoring.
How quickly could this interaction happen?
The documented onset is "unspecified". The timing of this interaction is not well characterized.
How strong is the evidence for this interaction?
The evidence is graded "theoretical". Predicted from the drugs' pharmacology; not yet confirmed in people.
From our Q&A
Real reader questions about these medications, each personally answered by our pharmacist:
Questions for your pharmacist
- Does my dose of Dutasteride 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 (1)
- Product Information: SPORANOX(R) oral capsules, itraconazole oral capsules. Janssen Pharmaceuticals Inc (per FDA), Titusville, NJ, 2022. DailyMed
Keep reading about Itraconazole
These medications also interact with supplements
Prescription drugs aren't the whole picture — herbal and dietary supplements can interact with them too. From the evidence-graded Natural Medicines database:
major · moderate · minor — check everything you take with our drug–supplement interaction checker.
Check another combination
Our instant two-drug interaction checker is almost here.
Still have questions about this combination?
Every question gets a real answer from a licensed pharmacist — free, and usually within a day.
Ask the pharmacist