Drug Interaction Report

Deutetrabenazine and Duloxetine: Interaction Details

A pharmacist-reviewed analysis of the Deutetrabenazine and Duloxetine 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

Duloxetine

No brand names on record
+

Deutetrabenazine

Austedo Austedo XR® Austedo®
Dr. Brian Staiger, PharmD, BCPS
Medically reviewed by
Dr. Brian Staiger, PharmD, BCPS
Updated Aug 8, 2026
Editorial policy · Data sources
LinkedIn
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 262 documented Deutetrabenazine interactions, 233 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
probable
Severity
Major

What happens

Increased CYP2D6 substrate exposure

Interaction Deep Dive

Concomitant use of DULoxetine increases the plasma concentrations of a drug primarily metabolized by CYP2D6 which may increase the risk of toxicity of the CYP2D6 substrate drug. Monitor plasma concentrations of CYP2D6 substrate and reduce dosage of CYP2D6 substrate drug if necessary12.

Why it happens (mechanism)

Inhibition of CYP2D6-mediated metabolism by DULoxetine

Literature reports

1 report — tap to read

a) When DULoxetine a CYP2D6 inhibitor was administered (at a dose of 60 mg twice daily) in conjunction with a single 50 mg dose of desipramine, a CYP2D6 substrate, the AUC of desipramine increased by 3-fold 12.

Common questions

Can I take Deutetrabenazine and Duloxetine together?

Increased CYP2D6 substrate exposure Always confirm with your pharmacist or prescriber before making any change.

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

From our Q&A

Real reader questions about these medications, each personally answered by our pharmacist:

Questions for your pharmacist

  • Does my dose of Deutetrabenazine or Duloxetine 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: CYMBALTA(R) oral delayed-release capsules, duloxetine oral delayed-release capsules. Lilly USA LLC (per FDA), Indianapolis, IN, 2023. DailyMed
  2. Product Information: DRIZALMA SPRINKLE(TM) oral delayed-release capsules, duloxetine oral delayed-release capsules. Sun Pharmaceuticals Industries Inc (per FDA), Cranbury, NJ, 2023. DailyMed
Was this write-up helpful?
Duloxetine

Keep reading about Duloxetine

All Duloxetine interactions (77)
Also serious with: Linezolid Injection Metoclopramide Nasal Spray Metoclopramide Injection Ketorolac Injection
Deutetrabenazine

Keep reading about Deutetrabenazine

All Deutetrabenazine interactions (262) Deutetrabenazine drug information
Also serious with: Isocarboxazid Linezolid Levoketoconazole Iproniazid
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:

Duloxetine + Activated Charcoal Beer Lithium Siberian Cocklebur Wine 1,3-dmaa 5-htp Acacia Rigidula + 124 more
Deutetrabenazine + 1,4-butanediol Activated Charcoal American Hellebore Arsenic Beer Cesium Ephedra Gamma-hydroxybutyrate (ghb) + 140 more

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.