Omeprazole and Cenobamate: Interaction Details
AI-assisted, pharmacist-reviewed · AI content regenerated Jul 11, 2026 · Source data updated Jul 2, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Cenobamate
Omeprazole
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.
You've been prescribed both cenobamate (Xcopri), a seizure medicine, and omeprazole (Prilosec) for acid reflux or heartburn. Cenobamate can slow down one of the liver enzymes that breaks omeprazole down. When that happens, more omeprazole can build up in your body, which may make its effects and any side effects (like headache, stomach upset, or diarrhea) a bit stronger.
The good news is this is expected mostly from how these drugs work on paper, not from big real-world problems. Please keep taking both as prescribed. Your care team can easily manage this by adjusting your omeprazole dose if needed and keeping an eye on how you feel.
Mechanism: Cenobamate is a CYP2C19 inhibitor; omeprazole is a CYP2C19 substrate (and itself a 2C19 inhibitor). Inhibition of CYP2C19-mediated metabolism may increase omeprazole exposure (AUC/Cmax) and the risk of dose-related adverse effects.
- Direction: Increased omeprazole exposure (inhibition, not a prodrug scenario here).
- Magnitude: Not quantified.
- Onset: Unspecified.
- Evidence: Theoretical.
- Management: Consider a reduction in the omeprazole (CYP2C19 substrate) dose when clinically appropriate; monitor for exaggerated or adverse PPI effects.
What happens
Increased exposure to CYP2C19 substrates and/or increased risk of adverse effects
Interaction Deep Dive
When cenobamate, which acts as an inhibitor of CYP2C19, is given together with a CYP2C19 substrate, the exposure to that substrate may rise and/or the likelihood of adverse effects related to the CYP2C19 substrate may be greater. If concurrent use with cenobamate cannot be avoided, reducing the dose of the CYP2C19 substrate may be considered where clinically appropriate1.
Why it happens (mechanism)
Inhibition of CYP2C19-mediated metabolism of CYP2C19 substrates
How to manage this interaction
This interaction can usually be handled without stopping either drug.
- Keep taking both cenobamate and omeprazole exactly as prescribed unless your prescriber tells you otherwise.
- Your care team may consider a lower omeprazole dose if it is clinically appropriate, and the dose can be individualized to you.
- They may also monitor you more closely for stronger-than-usual omeprazole effects or side effects.
Tell your pharmacist or doctor if you notice new or worsening symptoms such as headache, nausea, stomach upset, or diarrhea, and confirm your dosing plan with them.
Management is individual — confirm any change with your pharmacist or prescriber.
Common questions
Can I take Omeprazole and Cenobamate together?
Cenobamate can raise omeprazole levels by slowing its breakdown, so your care team may lower the omeprazole dose or watch you a bit more closely; keep taking both as prescribed and report any new side effects. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Omeprazole and Cenobamate interaction?
It is rated moderate. Can be significant — usually manageable with monitoring.
How quickly could this interaction happen?
The documented onset is "unspecified". The timing of this interaction is not well characterized.
How is the Omeprazole and Cenobamate interaction managed?
This interaction can usually be handled without stopping either drug. Keep taking both cenobamate and omeprazole exactly as prescribed unless your prescriber tells you otherwise. Your care team may consider a lower omeprazole dose if it is clinically appropriate, and the dose can be individualized to you. They may also monitor you more closely for stronger-than-usual omeprazole effects or side eff… Management is individual — always follow your own care team's guidance.
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 Omeprazole or Cenobamate 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 anything you'd monitor while I'm on both?
References (1)
- Product Information: XCOPRI(R) oral tablets, cenobamate oral tablets. SK Life Science Inc (per FDA), Paramus, NJ, 2024. DailyMed
Keep reading about Cenobamate
Keep reading about Omeprazole
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.
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