Drug interactions
Omeprazole + St john's wort
Severity: Moderate
Omeprazole and St john's wort: moderate interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
St John's wort induces omeprazole metabolism and can lower its plasma levels. This may weaken acid suppression, which is particularly relevant in H. pylori regimens or severe erosive disease.
What this interaction means in plain words
Omeprazole and St john's wort can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Why it happens
Induction of CYP2C19 and CYP3A4 by hyperforin increases omeprazole clearance.
What to do
Monitor for treatment failure and avoid the herbal product or increase the omeprazole dose if control is inadequate.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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Other interactions of Omeprazole
- Mavacamten + Omeprazole Contraindicated
- Omeprazole + Rilpivirine Contraindicated
- Acalabrutinib + Omeprazole Major
- Atazanavir + Omeprazole Major
- Citalopram + Omeprazole Major
- Clopidogrel + Omeprazole Major
Frequently asked questions
Can I take Omeprazole with St john's wort?
MediHelp rates the interaction as moderate. Omeprazole and St john's wort can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. St John's wort induces omeprazole metabolism and can lower its plasma levels. This may weaken acid suppression, which is particularly relevant in H. pylori regimens or severe erosive disease.
How serious is the interaction between Omeprazole and St john's wort?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor for treatment failure and avoid the herbal product or increase the omeprazole dose if control is inadequate.
What other medicines interact with Omeprazole?
MediHelp also lists interactions of Omeprazole with, for example, Mavacamten, Rilpivirine, Acalabrutinib. The full list is on the Omeprazole page.
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