Drug & supplement interaction

Bishop's Weed + Tisotumab Vedotin-Tftv

Tisotumab Vedotin-Tftv brand name: Tivdak.

Moderate Interaction
The bottom line Moderate

Bishop's Weed has a moderate interaction with Tisotumab Vedotin-Tftv. Bergapten, a constituent of bishop's weed, has been shown to inhibit cytochrome P450 3A4 (CYP3A4) in vitro.

Read the full interaction report
SeverityModerate
LikelihoodPossible
EvidenceB
What do Severity, Likelihood & Evidence mean?
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Interaction report

Bishop's Weed and Tisotumab Vedotin-Tftv

Here is the interaction we found between these two, with the evidence behind it.

Moderate

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES

Why this applies to Tisotumab Vedotin-Tftv

Tisotumab Vedotin-Tftv falls under CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES — the group Bishop's Weed interacts with.

Bergapten, a constituent of bishop's weed, has been shown to inhibit cytochrome P450 3A4 (CYP3A4) in vitro. Theoretically, bishop's weed might inhibit elimination and increase blood levels of drugs metabolized by CYP3A4.
Some drugs metabolized by CYP3A4 include alprazolam (Xanax), amitriptyline (Elavil), amiodarone (Cordarone), buspirone (Buspar), cerivastatin (Baycol), citalopram (Celexa), felodipine (Plendil), fexofenadine (Allegra), itraconazole (Sporanox), ketoconazole (Nizoral), lansoprazole (Prevacid), losartan (Cozaar), lovastatin (Mevacor), ondansetron (Zofran), prednisone (Deltasone, Orasone), sertraline (Zoloft), sibutramine (Meridia), sildenafil (Viagra), simvastatin (Zocor), verapamil (Calan, Covera-HS, Isoptin), and many others.
Severity Moderate Likelihood Possible Evidence B

Interaction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

Here's the idea behind this one. Bishop's Weed contains a compound called bergapten that may slow down a liver enzyme called CYP3A4. Since the small-molecule chemotherapy piece released from Tivdak (a payload called MMAE) is cleared in part through CYP3A4, blocking that pathway could let more of it build up in your body. That could mean stronger or more frequent side effects from this drug, like nausea, fatigue, hair loss, nerve tingling or numbness in the hands and feet, low blood counts, or eye irritation.

I'll be honest with you: this is mostly theoretical, based on lab tests rather than real patients. Still, Tivdak is a serious cancer treatment, so don't add Bishop's Weed on your own. Please run it by your oncology team first.

References
  1. Malhotra S, Bailey DG, Paine MF, Watkins PB. Seville orange juice-felodipine interaction: comparison with dilute grapefruit juice and involvement of furocoumarins. Clin Pharmacol Ther 2001;69:14-23. PubMed

What These Ratings Mean

Every interaction above is graded three ways — here’s the key to each label.

Severity how clinically significant the interaction is
Major

Clinically significant. Avoid the combination, or use only under close professional supervision.

Moderate

Usually worth avoiding or managing — may need monitoring, a dose change, or timing apart.

Minor

Generally not serious. Be aware of it and mention it to your pharmacist.

Likelihood how strong the evidence is that the interaction actually happens in people
  • LikelyWell-controlled human studies have demonstrated the likely existence of this interaction.
  • ProbableInteraction has not been documented in well-controlled studies, however, the interaction has been demonstrated in some small human studies or in controlled animal studies in conjunction with multiple case reports.
  • PossibleInteraction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.
  • UnlikelyInteraction has been demonstrated in animal or in lab research but has been shown not to occur in humans.
Evidence the quality of the studies behind the rating (graded A–D)
  • AHigh-quality meta-analysis (quantitative systematic review).
  • BCase-control study.
  • CConsensus.
  • DAnecdotal evidence.

These ratings are for information only. Never start, stop, or otherwise change your therapy before speaking with your provider.

Keep it in perspective

Bishop's Weed Also Interacts With Other Medications

Bishop's Weed has 953 moderate known drug interactions in our database — the Tisotumab Vedotin-Tftv one above is one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Bishop's Weed

Covers the 2,830 medications we’ve checked against Bishop's Weed. Pick one to open its full report.

Everything else you take

See Every Supplement That Interacts With Tisotumab Vedotin-Tftv

This page covers Bishop's Weed only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Tisotumab Vedotin-Tftv page lists 121 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Grapefruit (major), St. John's Wort (major), Acacia Rigidula (moderate), Adrafinil (moderate) and African Wild Potato (moderate).

By severity: 2 major · 87 moderate · 32 minor.

From our pharmacist’s overview on the Tisotumab Vedotin-Tftv page

“If you are receiving tisotumab vedotin (Tivdak), an infusion used to treat cervical cancer, treat this page with real care and clear every supplement with your oncology team first. All 121 ingredients here act through the same liver enzyme, CYP3A4, which processes the chemotherapy portion of this drug.”

Reviewed by 2 · Jul 18, 2026

Open the Tisotumab Vedotin-Tftv interaction page

One more smart check

Taking Bishop's Weed as Part of a Dietary Supplement Product? Check It for Interactions

We hold 83 real supplement products containing Bishop's Weed, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Bishop's Weed. Your product may carry other ingredients that interact with Tisotumab Vedotin-Tftv too, on top of Bishop's Weed — and those would not show on this page. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Bishop's Weed and Tisotumab Vedotin-Tftv Sit Against Everything Else

Out of every supplement and medication people look up on HelloPharmacist, here is where these two land this week — and which way each has been moving.

Supplement Bishop's Weed
Top half

#374 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Tisotumab Vedotin-Tftv
Top 5%

#136 of 2,830 medications looked up here in the last 7 days

29 days ago today

Position among everything looked up on this site, not a measure of how commonly either one is used or how important it is. A supplement can climb this list because of a news story. It counts every request to the page, automated ones included, and nothing here identifies anyone.

Supplement

About Bishop's Weed

What is Bishop's Weed?

Bishop's Weed
  • Vitiligo (loss of skin color)
  • Psoriasis
  • Digestive complaints
  • Asthma and breathing problems
  • Kidney stones
  • Diuretic (increasing urine)

Bishop's Weed (Ammi majus) is a flowering plant whose seeds contain natural light-sensitizing compounds called psoralens, which have been studied mainly for skin conditions like vitiligo and psoriasis when combined with light therapy. The plant is potentially toxic and can cause severe skin and eye reactions when exposed to sunlight, so it is not something to take on your own. If you are interested in psoralen-based treatments, work with a dermatologist rather than self-treating.

Read the full Bishop's Weed monograph & all interactions
Medication

About Tisotumab vedotin-tftv

What Is Tisotumab vedotin-tftv Used For?

Brand name: Tivdak

  • Tisotumab vedotin-tftv injection is used to treat cervical cancer (cancer that begins in the opening of the uterus [womb]) that has not improved or has come back after treatment with other medications or has spread to other parts of the body. Tisotumab vedotin-tftv is in a class of medications called antibody-drug conjugates. It works by killing cancer cells.

See full Tisotumab vedotin-tftv drug information
Keep checking

Other Drugs & Bishop's Weed

Browse every other medication we’ve checked against Bishop's Weed — both the ones with a known interaction and the ones without. Select any drug for the full detail.

0Major
953Moderate
0Minor
1,876No known interaction
Moderate

953 interactions

Showing 60 of 953 moderate interactions — see all 953 on the Bishop's Weed page.

No interaction 1,876 drugs checked — show the list
Sources

Sources & How We Checked

Interaction details are evidence-graded and sourced from the Natural Medicines database. The medication overview comes from MedlinePlus.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

Parts of this content are provided by the Therapeutic Research Center, LLC.

DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

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Pharmacist Counseling Corner

Taking Bishop's Weed and Tisotumab Vedotin-Tftv Together: Common Questions

Can you take Bishop's Weed with Tisotumab Vedotin-Tftv?
There is a moderate interaction, so it may be acceptable with monitoring or timing changes — but check with your pharmacist first. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Bishop's Weed and Tisotumab Vedotin-Tftv interaction?
We rate it Moderate. This combination may require monitoring, a dose adjustment, or separating the times you take each one. Consult your pharmacist before using them together.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

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This information is for education only and is not a substitute for professional medical advice. Always check with your pharmacist or doctor before starting, stopping, or combining supplements and medications.