Drug interactions
Amlodipine + St john's wort
Severity: Moderate
Amlodipine 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 CYP3A4 and P-glycoprotein, which may lower amlodipine concentrations and reduce its antihypertensive or antianginal effect. The effect may fade after the herb is stopped.
What this interaction means in plain words
Amlodipine 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 CYP3A4 by hyperforin increases amlodipine clearance.
What to do
Advise avoiding St John's wort, or monitor blood pressure and increase the amlodipine dose if needed. Reassess the dose after stopping the herb.
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 Amlodipine
- Amifostine + Amlodipine Major
- Amlodipine + Ombitasvir / paritaprevir / ritonavir and dasabuvir Major
- Activated Charcoal + Amlodipine Moderate
- Aldesleukin + Amlodipine Moderate
- Alfuzosin + Amlodipine Moderate
- Amlodipine + Apalutamide Moderate
Frequently asked questions
Can I take Amlodipine with St john's wort?
MediHelp rates the interaction as moderate. Amlodipine 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 CYP3A4 and P-glycoprotein, which may lower amlodipine concentrations and reduce its antihypertensive or antianginal effect. The effect may fade after the herb is stopped.
How serious is the interaction between Amlodipine 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: Advise avoiding St John's wort, or monitor blood pressure and increase the amlodipine dose if needed. Reassess the dose after stopping the herb.
What other medicines interact with Amlodipine?
MediHelp also lists interactions of Amlodipine with, for example, Amifostine, Ombitasvir / paritaprevir / ritonavir and dasabuvir, Activated Charcoal. The full list is on the Amlodipine page.
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