The short answer
Do not start St. John’s wort while taking entrectinib without the cancer team’s review. It can induce drug-metabolizing enzymes and may lower treatment exposure; a few hours of separation does not address this effect.
What this answer covers
Oral entrectinib with Hypericum perforatum preparations. Enzyme induction varies with product and repeated exposure.
- Supplement or preparation
- Hypericum perforatum
- Medication ingredient
- entrectinib
Check the exact treatment
This review concerns oral entrectinib in ROZLYTREK capsules or oral pellets for selected gene-fusion cancers. The medicine produces an active metabolite called M5. Follow the instructions for the prescribed formulation; a change in parent-drug levels does not automatically describe total active exposure.
Why exposure may fall
The entrectinib product information warns that CYP3A induction can lower the amount of medicine in the bloodstream and potentially impair treatment. St. John’s wort can produce that type of induction. This is a metabolic interaction, not a demonstrated reduction from supplements binding the medicine in the stomach.
Different products can have different effects
A study of six St. John’s wort preparations found different reductions in midazolam exposure, linked to hyperforin content. It did not test entrectinib. Its percentages cannot predict your drug level, and the same weight of two herbal products does not establish the same induction effect.
Coordinate changes with the cancer team
Tell the team about St. John’s wort in mood, sleep or combination products, including recent use or discontinuation. They should decide whether an alternative or extra monitoring is needed. Do not change the cancer-drug dose or assume a morning-evening gap prevents the interaction.
Evidence and practical considerations
Absorption & effectiveness
The exact drug’s CYP3A-inducer warning and human Hypericum probe evidence support a conditional reduced-exposure precaution.
- Exact scope
- Oral entrectinib with Hypericum perforatum preparations. Enzyme induction varies with product and repeated exposure. with RxNorm 2197862 IN entrectinib. Current exact oral product: ROZLYTREK oral entrectinib capsules and pellets. Salt/formulation named explicitly; no transfer to unrelated drugs or routes.
- Medication form and route
- Oral
What remains uncertain
- Exact drug inducer guidance plus indirect human Hypericum evidence. No exact botanical co-use effect size, response rate or validated spacing.
Factors that may matter: Exact oral formulation and supplement preparation; Drug exposure versus clinical outcomes; Dose, duration and other medicines; Individual monitoring plan.
Read the supporting source summaries
Source 1: Current original prescribing information
dailymed.nlm.nih.gov · Source check Sep 10, 2026
Population: Patients prescribed the exact oral formulation.
Avoid moderate/strong CYP3A inducers/inhibitors; parent drug and M5 exposure must be distinguished.
How this applies: RxNorm 2197862 IN entrectinib. Current exact oral product: ROZLYTREK oral entrectinib capsules and pellets. Salt/formulation named explicitly; no transfer to unrelated drugs or routes.
Exact current oral product source, not a clinical trial of every supplement. Formulation, dose, population and mechanism remain explicit.
Source 2: Original clinical research
pubmed.ncbi.nlm.nih.gov · Source check Sep 10, 2026
Population: 42 healthy men receiving six Hypericum preparations.
CYP3A induction varied with hyperforin dose; midazolam exposure decreased.
How this applies: Exact reported preparation, population and endpoints; transfer to entrectinib explicitly limited.
Abstract-only; not this exact cancer-drug combination. No transferable percentage or uniform low-hyperforin product effect.
Source 3: Medication terminology
rxnav.nlm.nih.gov · Source check Sep 10, 2026
Population: Terminology.
entrectinib is IN.
How this applies: Exact ingredient.
Not clinical evidence.
Research assessment: · Open full citations ↗
Review and change history
- Publication status
- Published research summary
- Clinical review
- Not yet recorded
| Date | Update |
|---|---|
| Research summary published | |
| Article prepared | |
| Sources checked and article drafted. |
Article revision: 919927fddf1b4c13
This guide brings together the evidence records used by our interaction checker. Each finding retains its own preparation limits, research date, and source summaries.
Full citations require verification. Reading this answer and the source summaries does not.
Taking other supplements or medications?
Use the checker to explore your other combinations. Ask a pharmacist to review the exact products, amounts and medical conditions in your complete list.
Open the interaction checkerInformation, not medical advice. Do not change prescribed treatment based on this guide.