Drug Interaction Report

Amlodipine and Atazanavir: Interaction Details

A pharmacist-reviewed analysis of the Amlodipine and Atazanavir interaction: the documented clinical effects, severity rating, onset, mechanism, and management considerations, with cited references throughout.

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

Atazanavir

Reyataz
+

Amlodipine

Amvaz® Katerzia Katerzia® Norliqva Norvasc Norvasc® Sdamlo
Dr. Brian Staiger, PharmD, BCPS
Medically reviewed by
Dr. Brian Staiger, PharmD, BCPS
Updated Aug 8, 2026
Editorial policy · Data sources
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Interaction severity
Major
Potentially serious — often needs a change or close monitoring.
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 195 documented Amlodipine interactions, 180 are rated major — 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
Major

What happens

Increased amLODIPine exposure and an increased risk of hypotension and edema

Interaction Deep Dive

Atazanavir, as an inhibitor of the isoenzyme CYP3A, may inhibit the metabolism of amLODIPine, a known CYP3A substrate. The combination of these drugs may result in increased amLODIPine exposure that could increase or prolong the adverse effects of amLODIPine. Monitor for symptoms of hypotension and edema when amLODIPine is coadministered with CYP3A inhibitors to determine the need for dose adjustment214. Caution is warranted with the concurrent use. Consider dose titration of amLODIPine and ECG monitoring is recommended 5.

Why it happens (mechanism)

Inhibition of CYP3A-mediated metabolism of amLODIPine

Literature reports

1 report — tap to read

a) In a pharmacokinetic study of elderly hypertensive patients, coadministration of dilTIAZem (a CYP3A inhibitor) 180 mg daily with amLODIPine 5 mg resulted in a 60% increase in amLODIPine systemic exposure 23.

Common questions

Can I take Amlodipine and Atazanavir together?

Increased amLODIPine exposure and an increased risk of hypotension and edema Always confirm with your pharmacist or prescriber before making any change.

How serious is the Amlodipine and Atazanavir 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 Amlodipine or Atazanavir 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 (5)

  1. Product Information: NORLIQVA(R) oral solution, amlodipine oral solution. CMP Pharma Inc (per FDA), Farmville, NC, 2022. DailyMed
  2. Product Information: WIDAPLIK(TM) oral tablets, telmisartan amlodipine indapamide oral tablets. George Medicines Pty Limited (per FDA), Pithampur, Pradesh, India, 2025. DailyMed
  3. Product Information: EXFORGE oral tablets, amlodipine valsartan oral tablets. Novartis Pharmaceuticals Corporation (per FDA), East Hanover, NJ, 2019. DailyMed
  4. Product Information: NORVASC(R) oral tablets, amlodipine besylate oral tablets. Pfizer Labs (per FDA), New York, NY, 2011. DailyMed
  5. Product Information: REYATAZ(R) oral capsules, oral powder, atazanavir oral capsules, oral powder. Bristol-Myers Squibb Company (per FDA), Princeton, NJ, 2020. DailyMed
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Atazanavir

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All Atazanavir interactions (179)
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Amlodipine

Keep reading about Amlodipine

All Amlodipine interactions (195) Amlodipine drug information
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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:

Atazanavir + Activated Charcoal Grapefruit St. John's Wort Acacia Rigidula Adrafinil African Wild Potato American Elder Astaxanthin + 144 more
Amlodipine + Activated Charcoal American Hellebore American Mistletoe Coleus Grapefruit St. John's Wort Tyramine Acacia Rigidula + 224 more

major · moderate · minor — check everything you take with our drug–supplement interaction checker.

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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.