Omeprazole and Saquinavir: 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
Saquinavir
No brand names on recordOmeprazole
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.
If you take saquinavir (an HIV medicine, usually boosted with ritonavir) together with omeprazole (a common acid reducer like Prilosec), the omeprazole can raise the amount of saquinavir in your blood. More saquinavir isn't always better, because higher levels can mean more side effects.
Things to watch for include stomach upset, higher triglycerides (a blood fat), and, less commonly, changes in your heart rhythm or blood clots in the legs. The good news: this is well known and very manageable. Your care team can check on you more closely and adjust your saquinavir dose if needed. Please don't stop either medicine on your own, just talk with your doctor or pharmacist.
Effect: Omeprazole increases exposure to ritonavir-boosted saquinavir (increased AUC and Cmax) in PK studies.
- Direction: Increased saquinavir levels (increased drug effect and toxicity risk).
- Mechanism: Unknown; not clearly attributable to a specific CYP or transporter pathway.
- Evidence: Established; severity major. Onset unspecified.
- Monitoring: Watch for saquinavir toxicities, GI symptoms, elevated triglycerides, QT prolongation (consider ECG), and DVT.
- Management: Coadminister with caution; reduce saquinavir dose if necessary based on tolerability and monitoring.
What happens
Increased saquinavir exposure
Interaction Deep Dive
When omeprazole is given together with ritonavir-boosted saquinavir, caution should be exercised, because a pharmacokinetic study showed that this combination produced marked rises in both saquinavir exposure and peak concentrations. While the two are taken concurrently, clinicians should watch patients for possible saquinavir-related toxicities, including gastrointestinal symptoms, elevated triglycerides, QT prolongation, and deep vein thrombosis3. Reducing the saquinavir dose may be required when it is used alongside omeprazole1.
Why it happens (mechanism)
Unknown
How to manage this interaction
Your care team can manage this safely. If both medicines are prescribed together, here is what typically happens:
- Keep taking both as prescribed unless your doctor or pharmacist tells you otherwise.
- Your team may monitor you more closely for stomach symptoms, higher triglycerides, heart-rhythm changes (QT prolongation), and signs of a leg blood clot (swelling, pain, redness).
- Your saquinavir dose may be adjusted and individualized by your care team if needed.
Tell your pharmacist or prescriber about any new stomach upset, leg swelling or pain, dizziness, or palpitations so they can act early.
Management is individual — confirm any change with your pharmacist or prescriber.
Literature reports
1 report — tap to read
a) In a pharmacokinetic study conducted in healthy volunteers (n=19), giving saquinavir 1000 mg/ritonavir 100 mg twice daily for 15 days together with omeprazole 40 mg once daily for 5 days produced increases of 82% (90% confidence interval (CI), 37% to 234%) in saquinavir AUC and 75% (90% CI, 31% to 234%) in saquinavir Cmax, respectively 4. and a 106% rise in Cmin 2.
Common questions
Can I take Omeprazole and Saquinavir together?
Omeprazole can significantly raise saquinavir levels, increasing the risk of side effects, so keep taking both as prescribed while your care team monitors you and adjusts your saquinavir dose if needed. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Omeprazole and Saquinavir 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 Saquinavir interaction managed?
Your care team can manage this safely. If both medicines are prescribed together, here is what typically happens: Keep taking both as prescribed unless your doctor or pharmacist tells you otherwise. Your team may monitor you more closely for stomach symptoms, higher triglycerides, heart-rhythm changes (QT prolongation), and signs of a leg blood clot (swelling, pain, redness). Your saquinavir dose… 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 Saquinavir 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)
- Product Information: PRILOSEC(R) oral delayed-release capsules, oral delayed-release suspension, omeprazole oral delayed-release capsules, omeprazole magnesium oral delayed-release suspension. AstraZeneca, Wilmington, PA, 2010. DailyMed
- Product Information: KONVOMEP(TM) powder for oral suspension, omeprazole sodium bicarbonate powder for oral suspension. Azurity Pharmaceuticals Inc (per manufacturer), Woburn, MA, 2022. DailyMed
- Product Information: INVIRASE(R) oral capsules, oral tablets, saquinavir mesylate oral capsules, oral tablets. Genentech USA, Inc (per FDA), South San Francisco, CA, 2012. DailyMed
- Product Information: INVIRASE(R) oral capsules, tablets, saquinavir mesylate oral capsules, tablets. Genentech USA, Inc. South San Francisco, CA, 2010. DailyMed
Keep reading about Saquinavir
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.
Check another combination
Our instant two-drug interaction checker is almost here.
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