Drug & supplement interaction

Bishop's Weed + Piroxicam

Piroxicam brand names: Feldene, Feldene Gel.

Moderate Interaction
Medically reviewed by · Updated September 2026
The bottom line Moderate

Piroxicam falls into 2 drug categories that Bishop's Weed can interact with; the most serious is rated moderate. Bishop's weed constituents seem to cause photosensitivity.

Read the full interaction report
SeverityModerate
LikelihoodPossible
Interactions2
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Bishop's Weed and Piroxicam

These two interact in 2 distinct ways. Each one is explained separately below.

Why Are There 2 Interactions?

Bishop's Weed interacts with whole categories of medication. Piroxicam falls into 2 of those categories, so it can interact with Bishop's Weed in 2 different ways. We’ve listed each one below — your overall risk is driven by the most serious of them (Moderate).

Moderate

PHOTOSENSITIZING DRUGS

1 of 2

Why this applies to Piroxicam

Piroxicam falls under PHOTOSENSITIZING DRUGS — the group Bishop's Weed interacts with.

Bishop's weed constituents seem to cause photosensitivity. Theoretically, concomitant use of bishop's weed with photosensitizing drugs might result in increased photosensitivity.
Some drugs that cause photosensitivity include amitriptyline (Elavil), quinolones (Ciprofloxacin, others), sulfa drugs (Septra, Bactrim, others), and tetracycline.
Severity Moderate Likelihood Possible Evidence D

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 thing about combining Bishop's Weed with piroxicam: both can make your skin more sensitive to sunlight. Piroxicam is an NSAID for arthritis pain and swelling, and one of its known quirks is that it can cause photosensitivity, meaning your skin sunburns more easily than usual. Bishop's Weed contains psoralens, which are powerful light-sensitizing compounds. Put the two together and you may stack that effect, leading to a faster, more intense sunburn, rash, or even blistering after time outdoors.

I'll be honest, this concern is mostly theoretical and based on anecdotal reports, so it's not a sure thing. Still, it's easy to play it safe with sunscreen and covered skin. Please check with your pharmacist or doctor before pairing these.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Ossenkoppele PM, van der Sluis WG, van Vloten WA. [Phototoxic dermatitis following the use of Ammi majus fruit for vitiligo]. Ned Tijdschr Geneeskd 1991;135:478-80.
  2. Dr. Duke's Phytochemical and Ethnobotanical Databases. Available at: http://www.ars-grin.gov/duke/.
Moderate

ANTICOAGULANT/ANTIPLATELET DRUGS

2 of 2

Piroxicam also falls under ANTICOAGULANT/ANTIPLATELET DRUGS.

Bergapten, a constituent of bishop's weed, has antiplatelet activity. Theoretically, bishop's weed might have additive effects with anticoagulant or antiplatelet drugs and possibly increase the risk of bleeding.
Some anticoagulant or antiplatelet drugs include aspirin, clopidogrel (Plavix), dalteparin (Fragmin), enoxaparin (Lovenox), heparin, ticlopidine (Ticlid), warfarin (Coumadin), and others.
Severity Moderate Likelihood Possible Evidence D

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 connection worth knowing about. Piroxicam is an NSAID, and like other NSAIDs it can thin the blood a little and irritate the stomach lining, which on its own raises bleeding risk. Bishop's Weed contains a compound called bergapten that may have a mild blood-thinning (antiplatelet) effect of its own. Put them together, and in theory those effects could stack up and make bleeding or bruising a bit more likely.

I want to be straight with you: this is a theoretical concern based on how these compounds behave, not something proven in real-world studies. Still, with Piroxicam, watch for signs like easy bruising, nosebleeds, dark or bloody stools, or stomach pain. Since Bishop's Weed isn't something to take on your own anyway, please run it by your pharmacist or doctor first.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Dr. Duke's Phytochemical and Ethnobotanical Databases. Available at: http://www.ars-grin.gov/duke/.

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 Piroxicam one above is among them. If you take anything else, check it against the full list below.

Moderate 953 No known interaction 1,877 (incl. Piroxicam)
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.

From our Q&A

Questions About Bishop's Weed or Piroxicam

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Bishop's Weed or Piroxicam, not necessarily both, but if one is close to what you were about to ask it will usually go further than a database entry can:

Not quite your question? Ask our pharmacists directly — it is free, there is no account required, and answers usually come back within 24 hours.

Everything else you take

See Every Supplement That Interacts With Piroxicam

This page covers Bishop's Weed only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Piroxicam page lists 285 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Asarabacca (major), Beer (major), Danshen (major) and Piracetam (major).

By severity: 7 major · 242 moderate · 36 minor.

From our pharmacist’s overview on the Piroxicam page

“Piroxicam (Feldene) is a potent, long-acting NSAID for arthritis pain, and since it already carries real stomach-bleeding risk on its own, my honest read is that this page calls for genuine caution rather than a quick skim. Most of the 285 interacting supplements share a single problem: they thin the blood or blunt platelets, stacking…”

Reviewed by 2 · Jul 18, 2026

Open the Piroxicam 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 Piroxicam 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 Piroxicam 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

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

29 days ago today
Medication Piroxicam
Steady interest

#1,729 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 Piroxicam

What Is Piroxicam Used For?

Brand names: Feldene, Feldene Gel

Piroxicam capsules are used to relieve pain, swelling, and stiffness caused by osteoarthritis and rheumatoid arthritis. It targets inflammation at the source to help improve day-to-day comfort and movement.

Piroxicam is not a cure for either condition — it manages symptoms. Your prescriber will weigh the benefits against the risks and aim for the lowest effective dose for the shortest time needed.

See full Piroxicam 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
953 Moderate 1,876 No 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

We also checked Bishop's Weed against these medications and found no known interaction in our sources. Open any page to confirm.

Showing the 60 most looked-up of 1,876 medications checked with no known interaction — see the full Bishop's Weed list.

See the full Bishop's Weed interactions page
See every supplement checked against Piroxicam, ranked by severity
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

Keep exploring
Bishop's Weed monograph › Uses, safety, and every drug interaction in one place Piroxicam supplement interactions › Every supplement checked against Piroxicam, ranked by severity Piroxicam drug information › The full plain-English guide to this medication Supplement interaction checker › Check any supplement or product against your medications Browse medications A–Z › Every drug we've checked against herbs & supplements Ask a pharmacist › Free, personal answer from our licensed team
Pharmacist Counseling Corner

Taking Bishop's Weed and Piroxicam Together: Common Questions

Can you take Bishop's Weed with Piroxicam?
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.
Why are there 2 interactions listed for Bishop's Weed and Piroxicam?
Piroxicam belongs to more than one drug category, and Bishop's Weed interacts with each of those categories a little differently. We list every one so nothing is missed — your overall risk is driven by the most serious of them.
How serious is the Bishop's Weed and Piroxicam 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

Still Have a Question About Piroxicam and Bishop's Weed?

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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.