Drug Interaction Report

Atazanavir and Lurasidone: Interaction Details

A pharmacist-reviewed analysis of the Atazanavir and Lurasidone 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
+

Lurasidone

Latuda Latuda®
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
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 179 documented Atazanavir interactions, 18 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
probable
Severity
Contraindicated

What happens

Increased lurasidone exposure

Interaction Deep Dive

Concurrent use of lurasidone (a CYP3A4 substrate) with a moderate CYP3A4 inhibitor may increase the exposure of lurasidone. In a pharmacokinetic study, coadministration of a single dose of lurasidone 20 mg with dilTIAZem (a moderate CYP3A4 inhibitor) 240 mg/day resulted in an approximate 2-fold increase in lurasidone Cmax and AUC2. Coadministration of atazanavir with ritonavir and lurasidone is contraindicated due to the potential for serious and/or life-threatening reactions. If coadministration of atazanavir without ritonavir is necessary, reduce the lurasidone dose 3. Therefore, when a moderate CYP3A4 inhibitor is added to lurasidone therapy, reduce the lurasidone dose to half of the original dose level. When lurasidone is added to therapy including a moderate CYP3A4 inhibitor, initiate lurasidone at 20 mg/day and do not exceed 80 mg/day 1. Coadministration of atazanavir with cobicistat and lurasidone is contraindicated due to the potential for serious and/or life-threatening reactions 4.

Why it happens (mechanism)

Inhibition of CYP3A4-mediated lurasidone metabolism by atazanavir

Common questions

Can I take Atazanavir and Lurasidone together?

Increased lurasidone exposure Always confirm with your pharmacist or prescriber before making any change.

How serious is the Atazanavir and Lurasidone 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 "probable". Good supporting evidence, though not definitively proven.

Questions for your pharmacist

  • Does my dose of Atazanavir or Lurasidone 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 (4)

  1. Product Information: LATUDA(TM) oral tablets, lurasidone HCl oral tablets. Sunovion Pharmaceuticals, Inc. (per manufacturer), Marlborough, MA, 2013. DailyMed
  2. Product Information: LATUDA(R) oral tablets, lurasidone HCl oral tablets. Sunovion Pharmaceuticals Inc. Fort Lee, NJ, 2010. DailyMed
  3. Product Information: REYATAZ(R) oral capsules, oral powder, atazanavir oral capsules, oral powder. Bristol-Myers Squibb Company (per FDA), Princeton, NJ, 2020. DailyMed
  4. Product Information: EVOTAZ(R) oral tablets, atazanavir cobicistat oral tablets. Bristol-Myers Squibb Company (per FDA), Princeton, NJ, 2023. DailyMed
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Atazanavir

Keep reading about Atazanavir

All Atazanavir interactions (179)
Also serious with: Encorafenib Irinotecan Lipid Complex Injection Colchicine Lovastatin
Lurasidone

Keep reading about Lurasidone

All Lurasidone interactions (135) Lurasidone drug information
Also serious with: Apalutamide Metoclopramide Nasal Spray Metoclopramide Injection Boceprevir
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
Lurasidone + Activated Charcoal Grapefruit Indian Snakeroot Rauvolfia Vomitoria St. John's Wort Acacia Rigidula Adrafinil African Wild Potato + 141 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.