Raltegravir and Omeprazole: 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
Raltegravir
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.
Here's what's going on. Omeprazole (Prilosec) lowers the acid in your stomach. Raltegravir (Isentress), your HIV medicine, actually dissolves and absorbs better when the stomach is less acidic. So taking them together can raise the amount of raltegravir in your blood.
The good news is that studies show these two can be taken together and no dose change is usually needed. Your care team may just keep an eye out for signs that raltegravir levels are running high, like stomach upset, muscle aches, or feeling unusually tired. Keep taking both as prescribed, and let your pharmacist or doctor know about any new symptoms. This is very manageable.
Effect: Increased raltegravir exposure (higher AUC/Cmax) with concurrent omeprazole.
Mechanism: Omeprazole raises gastric pH, increasing the pH-dependent solubility and absorption of raltegravir (a pH-sensitive integrase inhibitor). Neither agent is dependent on the other for activation.
- Direction: Raltegravir concentrations increased (PK interaction).
- Onset: Unspecified.
- Evidence: Established; clinical data support coadministration.
- Management: No raltegravir dose adjustment recommended. Monitor for raltegravir toxicity: GI symptoms, myopathy/rhabdomyolysis (consider CK if symptomatic), anemia and neutropenia (CBC).
What happens
Increased serum raltegravir concentrations
Interaction Deep Dive
Exercise caution when omeprazole and raltegravir are given together, since this combination can substantially raise raltegravir exposure and serum levels. This effect is probably driven by omeprazole raising gastric pH, which enhances the solubility and absorption of raltegravir1. Clinical evidence backs coadministering raltegravir with omeprazole without requiring any dose modification2. When concurrent use with omeprazole cannot be avoided, watch patients for possible raltegravir toxicities, including gastrointestinal symptoms, myopathy and rhabdomyolysis, as well as anemia and neutropenia.
Why it happens (mechanism)
Increased solubility and absorption of raltegravir due to increase in gastric pH
How to manage this interaction
What your care team typically does:
- Keeps both medicines going, since no raltegravir dose change is recommended when it is combined with omeprazole.
- Watches you a bit more closely for signs that raltegravir levels are elevated.
What you can do:
- Keep taking both exactly as prescribed unless your prescriber tells you otherwise.
- Report new or worsening stomach symptoms, unexplained muscle pain or weakness, unusual tiredness, paleness, or frequent infections to your pharmacist or doctor.
- Do not start or stop the omeprazole on your own; check with your care team first.
Management is individual — confirm any change with your pharmacist or prescriber.
Literature reports
1 report — tap to read
a) In a randomized, 2-period, single blind, crossover trial (n=14; mean age 41 years) involving healthy men and women, giving omeprazole together with raltegravir led to higher plasma levels of raltegravir, showing a 3 to 4 fold rise in both AUC and Cmax. Participants were randomly assigned to receive either 4 days of placebo followed by a single 400 mg dose of raltegravir administered in the fasted state on day 5, or 4 days of placebo doses along with omeprazole 20 mg once daily, followed by raltegravir 400 mg taken 2 hours after a 20 mg omeprazole dose in the fasted state on day 5. Plasma specimens were collected before treatment and for up to 72 hours after the raltegravir dose. A 3 to 4 fold increase was seen in the AUC (34.2 vs 11 micromol/L/hr) and Cmax (11.9 vs 2.88 micromol/L) in the raltegravir/omeprazole group relative to the raltegravir group. Omeprazole produced a minor effect on the raltegravir concentration at 12 hours (117 vs 80.6 nanomole/L for the raltegravir/omeprazole and raltegravir groups, respectively), and comparable half-life values were observed in both treatment groups 1.
Common questions
Can I take Raltegravir and Omeprazole together?
Omeprazole can raise raltegravir levels by reducing stomach acid, but they can be taken together without a dose change while your team watches for raltegravir side effects. Keep taking both as prescribed and report any new muscle pain, stomach upset, or unusual fatigue. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Raltegravir and Omeprazole 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 Raltegravir and Omeprazole interaction managed?
What your care team typically does: Keeps both medicines going, since no raltegravir dose change is recommended when it is combined with omeprazole. Watches you a bit more closely for signs that raltegravir levels are elevated. What you can do: Keep taking both exactly as prescribed unless your prescriber tells you otherwise. Report new or worsening stomach symptoms, unexplained muscle pain or wea… 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 Raltegravir 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 (2)
Keep reading about Raltegravir
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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