Drug Interaction Report

Midazolam Injection and Omeprazole: Interaction Details

A pharmacist-reviewed analysis of the Midazolam Injection and Omeprazole 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

Midazolam Injection

Nayzilam Versed® Injection
+

Omeprazole

Gastrobim Prilosec Prilosec® Prilosec® OTC Primeguard Talicia (as a combination product containing Amoxicillin, Omeprazole, Rifabutin) UlcerGard
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
Moderate
Can be significant — usually manageable with 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 276 documented Midazolam Injection interactions, 52 are rated moderate — including this one.
Onset
delayed
Evidence
theoretical
Severity
Moderate

What happens

Benzodiazepine toxicity (CNS depression, ataxia, lethargy)

Interaction Deep Dive

Concurrent use of diazepam and omeprazole has been reported to slow diazepam metabolism and delay its elimination, thereby resulting in enhanced and prolonged benzodiazepine effects123. One study indicated that decreased diazepam clearance occurred in almost half of patients who were fast metabolizers of omeprazole but the combination had little significance in slow metabolizers of omeprazole 4. Although not yet reported for combined midazolam-omeprazole therapy, similar effects would be expected to occur. Lorazepam, oxazepam, and temazepam are benzodiazepines that are metabolized by glucuronidation rather than by the cytochrome P450 enzyme system and may be good alternatives for patients needing omeprazole and benzodiazepine therapy.

Why it happens (mechanism)

Slowed benzodiazepine metabolism and clearance

Common questions

Can I take Midazolam Injection and Omeprazole together?

Benzodiazepine toxicity (CNS depression, ataxia, lethargy) Always confirm with your pharmacist or prescriber before making any change.

How serious is the Midazolam Injection and Omeprazole interaction?

It is rated moderate. Can be significant — usually manageable with monitoring.

How quickly could this interaction happen?

The documented onset is "delayed". Effects tend to build up gradually over days to weeks.

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 Midazolam Injection or Omeprazole 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 (4)

  1. Product Information: Prilosec(R), omeprazole. Astra Merck Inc. Wayne, PA, 1997. DailyMed
  2. Gugler R & Jensen JC: Omeprazole inhibits elimination of diazepam (letter). Lancet 1984; 1:969. PubMed
  3. von Herrath D & Thimme W: Wechselwirkungen von omeprazole und cimetidine mit diazepam. Der Arzneimittelbrief 1993; 27:87.
  4. Andersson T, Cederberg C, Edvardsson G, et al: Effect of omeprazole treatment on diazepam plasma levels in slow versus normal rapid metabolizers of omeprazole. Clin Pharmacol Ther 1990; 47:79-85. DOI
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Midazolam Injection

Keep reading about Midazolam Injection

All Midazolam Injection interactions (276) Midazolam Injection drug information
Also serious with: Nelfinavir Nirmatrelvir Ritonavir Saquinavir
Omeprazole

Keep reading about Omeprazole

All Omeprazole interactions (142) Omeprazole drug information
Also serious with: Ensitrelvir Rilpivirine Octreotide Injection Diazepam Rectal
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:

Omeprazole + Activated Charcoal Grapefruit St. John's Wort Acacia Rigidula Adrafinil African Wild Potato American Elder Artichoke + 166 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.