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Drug interactions

Brentuximab + St john's wort

Severity: Moderate

Brentuximab 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 may lower MMAE exposure from brentuximab vedotin, possibly reducing efficacy. The size of the effect varies with the herbal product.

What this interaction means in plain words

Brentuximab 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.

Evidence level: Low

Why it happens

Induction of CYP3A4 increases MMAE clearance.

What to do

Advise patients to avoid St John's wort during brentuximab treatment.

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?

Bring a full list of your medicines, including over-the-counter products, supplements and herbal remedies, to every pharmacy visit.

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Frequently asked questions

Can I take Brentuximab with St john's wort?

MediHelp rates the interaction as moderate. Brentuximab 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 may lower MMAE exposure from brentuximab vedotin, possibly reducing efficacy. The size of the effect varies with the herbal product.

How serious is the interaction between Brentuximab 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 patients to avoid St John's wort during brentuximab treatment.

What other medicines interact with Brentuximab?

MediHelp also lists interactions of Brentuximab with, for example, Bleomycin, Dengue vaccine, Etrasimod. The full list is on the Brentuximab page.

Full monographs, dosing and an interaction checker in the MediHelp app

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