Drug Interaction Report

Indinavir and Alfuzosin: Interaction Details

AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature

Indinavir

No brand names on record
+

Alfuzosin

UroXatral Uroxatral®
Dr. Brian Staiger, PharmD, BCPS
Medically reviewed by
Updated Aug 8, 2026
LinkedIn
Interaction severity
Contraindicated
These should generally not be used together.
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.

Of 123 documented Indinavir interactions, 14 are rated contraindicated — including this one.
Worried about symptoms right now? Contact your pharmacist or prescriber, or call Poison Control at 1-800-222-1222 (US). Call 911 for an emergency.
Onset
unspecified
Evidence
theoretical
Severity
Contraindicated

What happens

Increased alfuzosin plasma concentrations

Interaction Deep Dive

Although the interaction between alfuzosin, a CYP3A4 substrate, and indinavir, a potent CYP3A4 inhibitor, has not been studied, the interaction between alfuzosin and ketoconazole, another potent CYP3A4 inhibitor, resulted in 2- to 3-fold increases in alfuzosin Cmax and AUC values1. Therefore, concomitant use of alfuzosin and indinavir is contraindicated due to the potential for significant increases in alfuzosin plasma concentrations, which could result in hypotension 2.

Why it happens (mechanism)

Inhibition of CYP3A4-mediated alfuzosin metabolism by indinavir

Literature reports

1 report — tap to read

a) Although the interaction between alfuzosin, a CYP3A4 substrate, and indinavir, a potent CYP3A4 inhibitor, has not been studied, there have been two studies in which repeated doses of ketoconazole, another potent CYP3A4 inhibitor, and alfuzosin resulted in increased alfuzosin Cmax and AUC values. In one study, alfuzosin Cmax and AUC were increased by 2.3- and 3.2-fold, respectively, when patients received repeated ketoconazole doses of 400 mg/day followed by a single 10-mg alfuzosin dose. In another study, alfuzosin Cmax and AUC were increased by 2.1- and 2.5-fold when patients received repeated ketoconazole doses of 200 mg/day followed by a single 10-mg alfuzosin dose 1.

Common questions

Can I take Indinavir and Alfuzosin together?

Increased alfuzosin plasma concentrations Always confirm with your pharmacist or prescriber before making any change.

How serious is the Indinavir and Alfuzosin interaction?

It is rated contraindicated. These should generally not be used together.

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.

Questions for your pharmacist

  • Does my dose of Indinavir or Alfuzosin 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 (2)

  1. Product Information: UROXATRAL(R) extended release oral tablets, alfuzosin hcl extended release oral tablets. Sanofi-Aventis, Bridgewater, NJ, 2010.
  2. Product Information: CRIXIVAN(R) oral capsules, indinavir sulfate oral capsules. Merck & Co, Inc, Whitehouse Station, NJ, 2010. DailyMed
Was this write-up helpful?
Beyond drug–drug

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.

Coming soon

The instant two-drug checker is on its way.

In the meantime, browse the directory below to look up any drug and see its documented interactions.

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
This information is for education, not a substitute for professional medical advice. Do not start, stop, or change any medication without talking to your pharmacist or prescriber.