Drug & supplement interaction

Bismuth + Fondaparinux

Fondaparinux brand name: Arixtra.

Moderate Interaction
The bottom line Moderate

Bismuth has a moderate interaction with Fondaparinux. Theoretically, use of bismuth subgallate or other bismuth salts might reduce the effects of anticoagulant/antiplatelet drugs.

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

Bismuth and Fondaparinux

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

Moderate

ANTICOAGULANT/ANTIPLATELET DRUGS

Why this applies to Fondaparinux

Fondaparinux falls under ANTICOAGULANT/ANTIPLATELET DRUGS — the group Bismuth interacts with.

Theoretically, use of bismuth subgallate or other bismuth salts might reduce the effects of anticoagulant/antiplatelet drugs.
In humans, bismuth subgallate activates factor XII and accelerates the coagulation cascade.
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 idea behind this one. Fondaparinux (Arixtra) is a blood thinner you inject to keep dangerous clots from forming. Bismuth, the kind found in some stomach remedies, may slightly push your blood in the opposite direction. In studies, bismuth subgallate can switch on a clotting protein (factor XII) and speed up the clotting process. So in theory, regular bismuth use could blunt how well your fondaparinux works, meaning a bit more clotting risk.

I want to be honest though: this is a theoretical concern based on how these things behave, not on cases of people actually having problems. An occasional dose for an upset stomach is unlikely to undo your blood thinner. Still, since fondaparinux is keeping a clot from forming, please check with your pharmacist or doctor before using bismuth regularly.

References
  1. Callanan, V., Curran, A. J., Smyth, D. A., and Gormley, P. K. The influence of bismuth subgallate and adrenaline paste upon operating time and operative blood loss in tonsillectomy. J Laryngol Otol 1995;109(3):206-208. 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

Bismuth Also Interacts With Other Medications

Bismuth has 124 moderate known drug interactions in our database — the Fondaparinux 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 Bismuth

Covers the 2,830 medications we’ve checked against Bismuth. Pick one to open its full report.

Everything else you take

See Every Supplement That Interacts With Fondaparinux

This page covers Bismuth only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Fondaparinux page lists 202 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Danshen (major), Piracetam (major), Aconite (moderate), Allspice (moderate) and Aloe (moderate).

By severity: 2 major · 183 moderate · 17 minor.

From our pharmacist’s overview on the Fondaparinux page

“Most people on fondaparinux (Arixtra) are recovering from surgery or treating a blood clot, exactly the moment supplements for circulation and recovery come out of the cabinet. This pairing deserves real care, because nearly all 202 ingredients on this list share one problem: they thin the blood a little on their own, so adding them to…”

Reviewed by 2 · Jul 18, 2026

Open the Fondaparinux interaction page

One more smart check

Taking Bismuth as Part of a Dietary Supplement Product? Check It for Interactions

We hold 65 real supplement products containing Bismuth, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Bismuth. Your product may carry other ingredients that interact with Fondaparinux too, on top of Bismuth — 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 Bismuth and Fondaparinux 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 Bismuth
Top half

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

29 days ago today
Medication Fondaparinux
Top 10%

#157 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 Bismuth

What is Bismuth?

  • Upset stomach and indigestion
  • Diarrhea
  • Heartburn and nausea
  • Helicobacter pylori treatment (with other drugs)
  • Traveler's diarrhea prevention

Bismuth is a metallic element used in medicine mostly as bismuth subsalicylate (the active ingredient in some well-known stomach remedies) to ease upset stomach, heartburn, nausea, and diarrhea. It is generally well tolerated for short-term use, but it can cause harmless black stools or a dark tongue, and because most products contain salicylate, it carries cautions similar to aspirin. Always follow the label and check with a pharmacist before regular use.

Read the full Bismuth monograph & all interactions
Medication

About Fondaparinux Injection

What Is Fondaparinux Injection Used For?

Brand name: Arixtra

Fondaparinux sodium injection is used to prevent deep vein thrombosis (DVT) — blood clots that form in the legs — in adults who are having hip fracture surgery, hip replacement surgery, knee replacement surgery, or abdominal surgery. Preventing these clots also lowers the risk of a clot traveling to the lungs (pulmonary embolism, or PE).

It is also used to treat acute DVT and acute pulmonary embolism in adults, typically started alongside warfarin. In children aged 1 year and older who weigh at least 10 kg (about 22 lbs), fondaparinux sodium injection is approved to treat venous thromboembolism (VTE) — blood clots in the veins.

See full Fondaparinux Injection drug information
Keep checking

Other Drugs & Bismuth

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

0Major
124Moderate
0Minor
2,705No known interaction
Moderate

124 interactions

Showing 60 of 124 moderate interactions — see all 124 on the Bismuth page.

No interaction 2,705 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 Bismuth and Fondaparinux Together: Common Questions

Can you take Bismuth with Fondaparinux?
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 Bismuth and Fondaparinux 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.