Omeprazole and Ritonavir: 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
Ritonavir
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.
What's going on: Ritonavir (Norvir) can lower the amount of omeprazole (Prilosec) in your blood. Omeprazole is the medicine that quiets stomach acid, so if levels drop, it may not control your heartburn, reflux, or ulcer symptoms as well as it should.
The good news is this is very manageable. Your care team can watch how well your symptoms are controlled and, if needed, adjust your omeprazole dose to keep you comfortable. Please don't stop or change either medicine on your own. Just let your pharmacist or doctor know if your stomach symptoms come back or get worse.
Effect: Concomitant ritonavir reduces omeprazole plasma exposure, potentially lowering acid-suppression efficacy.
- Direction: Reduced omeprazole effect (decreased concentrations/AUC).
- Mechanism: Unknown per available data; likely enzyme-related given ritonavir's mixed CYP effects, but not established.
- Onset: Unspecified.
- Evidence: Established, severity rated major.
Management: Monitor for loss of omeprazole efficacy (recurrent reflux, dyspepsia, ulcer symptoms). Dose may be increased and individualized in symptomatic patients, but avoid omeprazole doses greater than 40 mg/day. Reassess symptom control periodically.
What happens
Decreased omeprazole exposure
Interaction Deep Dive
Taking ritonavir together with omeprazole can lead to reduced omeprazole plasma levels. Watch for a loss of omeprazole effectiveness, and in patients who remain symptomatic, a higher dose may be warranted. Do not administer omeprazole at doses exceeding 40 mg/day1.
Why it happens (mechanism)
Unknown
How to manage this interaction
Keep taking both medicines as prescribed unless your prescriber tells you otherwise. The main thing here is watching whether your omeprazole is still doing its job.
- Tell your care team if reflux, heartburn, or ulcer-type symptoms return or worsen.
- Your omeprazole dose may need to be adjusted and individualized by your care team if symptoms break through.
- Doses of omeprazole above 40 mg per day are generally avoided with ritonavir, so let your team decide any changes.
- Bring an updated medication list to appointments so your team can monitor this.
Management is individual — confirm any change with your pharmacist or prescriber.
Literature reports
1 report — tap to read
a) When omeprazole 40 mg once daily was given together with ritonavir (combined with ombitasvir, paritaprevir, and dasabuvir), the Cmax and AUC of omeprazole were reduced by 38% 1.
Common questions
Can I take Omeprazole and Ritonavir together?
Ritonavir can lower omeprazole levels and weaken its acid control, so watch for returning stomach symptoms and let your care team adjust the dose if needed (staying at or below 40 mg/day). Always confirm with your pharmacist or prescriber before making any change.
How serious is the Omeprazole and Ritonavir 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 is the Omeprazole and Ritonavir interaction managed?
Keep taking both medicines as prescribed unless your prescriber tells you otherwise. The main thing here is watching whether your omeprazole is still doing its job. Tell your care team if reflux, heartburn, or ulcer-type symptoms return or worsen. Your omeprazole dose may need to be adjusted and individualized by your care team if symptoms break through. Doses of omeprazole above 40 mg per day are… Management is individual — always follow your own care team's guidance.
How strong is the evidence for this interaction?
The evidence is graded "established". Well documented — supported by controlled studies or strong clinical data.
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 Ritonavir 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 (1)
- Product Information: VIEKIRA PAK oral tablets, ombitasvir paritaprevir ritonavir oral tablets and dasabuvir oral tablets. AbbVie Inc. (per manufacturer), North Chicago, Il, 2014.
Keep reading about Ritonavir
Keep reading about Omeprazole
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