The short answer
Do not start St. John’s wort while taking pirtobrutinib without the cancer team’s review. Its enzyme-inducing effects can lower drug exposure, and separating doses by a few hours does not address that concern.
What this answer covers
Oral pirtobrutinib with Hypericum perforatum products, distinguishing repeated enzyme induction from immediate gut binding.
- Supplement or preparation
- Hypericum perforatum
- Medication ingredient
- pirtobrutinib
Check the prescribed treatment
This review concerns oral pirtobrutinib tablets used for selected blood cancers. Pirtobrutinib is a reversible BTK inhibitor, and interaction findings or dose adjustments from other BTK medicines should not be copied to it. Keep your prescribed dosing and blood-count monitoring plan.
Why drug exposure may fall
The pirtobrutinib instructions warn about medicines that induce CYP3A and can lower drug exposure. St. John’s wort can produce this type of induction. That supports concern about treatment effectiveness, but is not a measured loss of absorption or a cancer-response estimate for a particular herbal brand.
The herbal product matters
A human study of six St. John’s wort preparations found different effects on a CYP3A probe, linked to hyperforin content. It did not test pirtobrutinib. A percentage measured with that probe cannot predict your cancer-drug level, and the same tablet weight does not guarantee the same induction.
Coordinate starting and stopping
Tell the team about recent or current St. John’s wort use, including mood or sleep blends. They should choose an alternative or monitoring plan. Do not adjust the cancer-drug dose or assume a morning-evening schedule prevents a metabolic interaction.
Evidence and practical considerations
Absorption & effectiveness
The exact drug’s CYP3A-inducer precaution and human Hypericum probe evidence support conditional avoidance/review.
- Exact scope
- Oral pirtobrutinib with Hypericum perforatum products, distinguishing repeated enzyme induction from immediate gut binding. with RxNorm 2629338 IN pirtobrutinib. Exact current oral product: JAYPIRCA oral pirtobrutinib tablets. Salt, formulation and regimen distinctions explicit.
- Medication form and route
- Oral
What remains uncertain
- No exact Hypericum co-use PK or outcome study. Label inducer guidance and preparation-specific human probe evidence are an indirect bridge; no validated spacing.
Factors that may matter: Exact oral formulation and supplement preparation; Drug exposure versus clinical outcomes; Dose and duration; Platelet count and neurological symptoms.
Read the supporting source summaries
Source 1: Current original prescribing information
dailymed.nlm.nih.gov · Source check Sep 11, 2026
Population: Patients prescribed the exact oral formulation.
Bleeding/cytopenia warnings; strong inhibitor AUC increase 49% and strong inducer reduction 71%; product-specific management.
How this applies: RxNorm 2629338 IN pirtobrutinib. Exact current oral product: JAYPIRCA oral pirtobrutinib tablets. Salt, formulation and regimen distinctions explicit.
Exact product source, not a direct study of every supplement. Population, active metabolites and formulation scope retained.
Source 2: Original clinical research
pubmed.ncbi.nlm.nih.gov · Source check Sep 11, 2026
Population: 42 healthy men receiving six Hypericum preparations.
CYP3A induction varied with hyperforin exposure.
How this applies: Exact preparation/population/endpoints only; applicability to pirtobrutinib independently assessed.
Abstract-only; no target drug or transferable exposure percentage.
Source 3: Medication terminology
rxnav.nlm.nih.gov · Source check Sep 11, 2026
Population: Terminology.
pirtobrutinib 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: ec099a371d905f06
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.