Ginkgo 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
Omeprazole
Ginkgo
No brand names on record
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 omeprazole (like Prilosec) for heartburn or reflux and you also use ginkgo supplements, they can work against each other. Ginkgo appears to speed up how your body breaks down omeprazole, so there is less omeprazole in your system to do its job. That means your stomach acid may not be controlled as well, and symptoms like heartburn could come back.
There is also a separate concern: taking ginkgo with omeprazole was linked to more bleeding in a study. The good news is this is very manageable. Please talk with your pharmacist or doctor before starting or stopping any supplement so they can keep an eye on your symptoms and safety.
Effect: Ginkgo biloba induces CYP2C19, increasing metabolism of omeprazole (a CYP2C19 substrate). Result is reduced omeprazole exposure (decreased AUC and Cmax) in a manner dependent on CYP2C19 genotype, with potential loss of acid-suppression efficacy. A separate signal shows increased bleeding and abnormal coagulation parameters with concomitant use.
- Direction: reduced omeprazole effect; increased bleeding risk
- Onset: rapid
- Evidence: probable
- Severity: moderate
Management: Monitor for breakthrough acid-related symptoms and signs of bleeding or abnormal coagulation. Dose may be individualized by the care team, or the supplement reconsidered.
What happens
Reduced omeprazole effectiveness and increased risk of bleeding
Interaction Deep Dive
Because taking ginkgo biloba together with omeprazole (a CYP2C19 substrate) can reduce how well omeprazole works, monitoring may be warranted. One study found that giving ginkgo biloba alongside omeprazole produced significant reductions in the mean AUC and Cmax of omeprazole, an effect that appeared to vary according to CYP2C19 genotype1. In a separate study, using ginkgo biloba together with omeprazole was associated with a significant rise in bleeding events and abnormal coagulation test results when compared with ginkgo biloba taken without any recognized interacting medications2.
Why it happens (mechanism)
Induction of CYP2C19-mediated metabolism of omeprazole by ginkgo biloba
How to manage this interaction
This interaction can be managed with your care team's help.
- Keep taking your omeprazole as prescribed and do not start or stop ginkgo on your own.
- Tell your pharmacist or prescriber that you use (or want to use) ginkgo so they can watch how well your reflux or heartburn is controlled.
- Your omeprazole dose may need to be adjusted and individualized by your care team if your symptoms return.
- Watch for signs of bleeding such as easy bruising, nosebleeds, or blood in stool, and report them promptly.
Management is individual — confirm any change with your pharmacist or prescriber.
Literature reports
2 reports — tap to read
a) In a retrospective observational study, giving ginkgo biloba together with at least 1 known interacting drug (drug-drug interaction group; n=258) was significantly associated with a higher frequency of bleeding (OR, 1.08; 95% CI, 1.04 to 1.11) and abnormal coagulation tests (OR, 1.49; 95% CI, 1.38 to 1.58) relative to subjects who received ginkgo biloba without any known interacting drugs (non-drug-drug interaction group; n=489). Significantly greater rates of bleeding and abnormal coagulation tests were seen with ginkgo biloba combined with clopidogrel (OR, 1.1 and 1.58), aspirin (OR, 1.12 and 1.48), or omeprazole (OR, 1.1 and 1.51), respectively. Coadministration of etoricoxib (OR, 1.37), insulin (OR, 1.34), or domperidone (OR, 1.29) significantly raised only the abnormal coagulation tests outcome; loxoprofen (OR, 1.58) or nifedipine (OR, 1.09) significantly raised only the bleeding outcome. No significant differences between groups were found for either outcome with ticagrelor, acenocoumarol, meloxicam, celecoxib, or direct oral anticoagulants (enoxaban or rivaroxaban). Patients had a mean age of roughly 63 years and were predominantly female (66.67%). Most patients had 1 interacting drug pair (71.71%), while 24.81% had 2, 2.71% had 3, and 0.77% had 4 interacting pairs 2.
b) Giving ginkgo biloba along with omeprazole appeared to significantly speed up omeprazole hydroxylation in a way that depended on CYP2C19 genotype. In an open-label pharmacokinetic study, healthy CYP2C19-genotyped Chinese male patients (n=18) received single oral doses of omeprazole 40 mg after an overnight fast. Following a washout of at least 4 weeks, each subject then took a 12-day course of oral ginkgo biloba 140 mg twice daily. On day 13, each subject received another single dose of omeprazole 40 mg, after the final dose of ginkgo biloba. Of the 18 patients, 6 were genotypically homozygous extensive metabolizers (EM), 5 were heterozygous EMs, and 7 were poor metabolizers (PM). After coadministration with ginkgo biloba, the mean Cmax of omeprazole and its sulfone metabolite were significantly reduced compared with control values; omeprazole Cmax fell by 30%, 39%, and 46% for homozygous EMs, heterozygous EMs, and PMs, respectively. Taking omeprazole together with ginkgo biloba significantly raised the mean Cmax of the 5-hydroxyomeprazole metabolite by approximately 61%, 80%, and 86% for homozygous EMs, heterozygous EMs, and PMs, respectively. Mean omeprazole AUC(0 to inf) dropped significantly in homozygous EMs, heterozygous EMs, and PMs by 41.5%, 27.2%, and 40.4%, respectively, compared with controls after ginkgo biloba coadministration. Omeprazole terminal half-life was also significantly shortened for all 3 metabolizer genotypes, as was the renal clearance of the 5-hydroxyomeprazole metabolite 1.
Common questions
Can I take Ginkgo and Omeprazole together?
Ginkgo can make omeprazole less effective for acid control and may add to bleeding risk, so let your pharmacist or doctor know if you use both and watch for returning heartburn or any unusual bleeding. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Ginkgo and Omeprazole interaction?
It is rated moderate. Can be significant — usually manageable with monitoring.
How quickly could this interaction happen?
The documented onset is "rapid". Effects can appear quickly, often within about 24 hours of combining the drugs.
How is the Ginkgo and Omeprazole interaction managed?
This interaction can be managed with your care team's help. Keep taking your omeprazole as prescribed and do not start or stop ginkgo on your own. Tell your pharmacist or prescriber that you use (or want to use) ginkgo so they can watch how well your reflux or heartburn is controlled. Your omeprazole dose may need to be adjusted and individualized by your care team if your symptoms return. Watch f… Management is individual — always follow your own care team's guidance.
How strong is the evidence for this interaction?
The evidence is graded "probable". Good supporting evidence, though not definitively proven.
From our Q&A
Real reader questions about these medications, each personally answered by our pharmacist:
Questions for your pharmacist
- Does my dose of Ginkgo 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)
- Yin OQP, Tomlinson B, Waye MMY, et al: Pharmacogenetics and herb-drug interactions: experience with Ginkgo biloba and omeprazole. Pharmacogenetics 2004; 14(12):841-850. PubMed
- Mai NTQ, Hieu NV, Ngan TT, et al: Impact of Ginkgo biloba drug interactions on bleeding risk and coagulation profiles: a comprehensive analysis. PLoS One 2025; 20(4):e0321804. PubMed
Keep reading about Omeprazole
Keep reading about Ginkgo
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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