Does Ketoconazole Interact With Tamsulosin?

7 DRUG INTERACTIONS • Tamsulosin hydrochloride capsules 0.4 mg should not be used with strong inhibitors of CYP3A4 (e.g., ketoconazole).

Severity: Major

Severity basis: drug interactions section (keywords: should not be used). Combining Ketoconazole (Azole antifungal (strong CYP3A4 inhibitor)) and Tamsulosin (Alpha-1 blocker (BPH)) is classified as a major interaction.

What to Do

The label advises avoiding this combination or using it only under close medical supervision. Talk to your prescriber or pharmacist before combining them.

From the FDA Label

7 DRUG INTERACTIONS • Tamsulosin hydrochloride capsules 0.4 mg should not be used with strong inhibitors of CYP3A4 (e.g., ketoconazole).

Source: FDA structured product labeling (set_id 00097e78-9c04-4e62-8260-ddb50e9a6a93).

Ketoconazole

Azole antifungal (strong CYP3A4 inhibitor)

Brands: Nizoral

View Ketoconazole safety profile

Tamsulosin

Alpha-1 blocker (BPH)

Brands: Flomax

View Tamsulosin safety profile

Check these against your full medication list in our free Interaction Checker

This information is educational — not medical advice.

This page is provided for general educational purposes and summarizes publicly available data from sources such as the U.S. Food & Drug Administration. It is not a substitute for the judgment of a licensed clinician and should not be used to start, stop, or change any medication. It may be incomplete or out of date, and individual circumstances vary. Always talk with your prescriber or pharmacist about your specific medications and health conditions. If you think you may have a medical emergency, call 911.

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