Drug & supplement interaction

Fulvic Acid + Fondaparinux

Fondaparinux brand name: Arixtra.

Moderate Interaction
The bottom line Moderate

Fulvic Acid has a moderate interaction with Fondaparinux. Theoretically, taking fulvic acid may decrease the effectiveness of anticoagulant and antiplatelet drugs.

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

Fulvic Acid 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 Fulvic Acid interacts with.

Theoretically, taking fulvic acid may decrease the effectiveness of anticoagulant and antiplatelet drugs.
In vitro evidence shows that fulvic acid, formed from the oxidation and polymerization of protocatechuic acid, can shorten prothrombin time in human plasma, increasing the risk of clot formation.
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 concern with combining these two. Fondaparinux (Arixtra) is a blood thinner that you inject to keep dangerous clots from forming, especially after hip or knee surgery. The worry is that fulvic acid might work in the opposite direction. In lab studies (test tube only, not in people), fulvic acid shortened the time it takes blood to clot, which could in theory blunt how well your blood thinner works.

If that happened, it could mean less protection against a clot, which is the whole reason you're on Fondaparinux. I want to be honest though: this is purely theoretical, based on lab data, not real patients. Still, with a clot-prevention medicine, I'd play it safe. Please check with your pharmacist or doctor before adding fulvic acid, and never stop your Fondaparinux on your own.

References
  1. Lu, FJ. Arsenic as a promoter in the effect of humic substances on plasma prothrombin time in vitro. Thromb Res 6-15-1990;58(6):537-541. 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

Fulvic Acid Also Interacts With Other Medications

Fulvic Acid has 256 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 Fulvic Acid

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

Everything else you take

See Every Supplement That Interacts With Fondaparinux

This page covers Fulvic Acid 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 Fulvic Acid as Part of a Dietary Supplement Product? Check It for Interactions

We hold 294 real supplement products containing Fulvic Acid, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Fulvic Acid. Your product may carry other ingredients that interact with Fondaparinux too, on top of Fulvic Acid — 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 Fulvic Acid 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 Fulvic Acid
Top half

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

29 days ago today
Medication Fondaparinux
Top half

#916 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 Fulvic Acid

What is Fulvic Acid?

  • General wellness and energy
  • Gut health
  • Antioxidant support
  • Mineral and nutrient supplementation
  • Immune support

Fulvic acid is a natural compound formed when plants and microbes break down in soil, and it is sold as a supplement for energy, gut, and overall wellness. Human research is very limited, so most claims are unproven. Talk with your pharmacist or doctor before using it, and avoid it during pregnancy and breastfeeding due to a lack of safety data.

Read the full Fulvic Acid monograph & all interactions
Medication

About Fondaparinux Injection

What Is Fondaparinux Injection Used For?

Brand name: Arixtra

Fondaparinux Injection helps prevent and treat dangerous blood clots. In adults, it is used to prevent deep vein thrombosis (DVT, a clot in a deep vein, usually in the leg) after hip fracture surgery, hip replacement, knee replacement or abdominal surgery.

It is also used with warfarin to treat acute DVT and acute pulmonary embolism (PE, a clot in the lungs) in adults. In children aged 1 year and older who weigh at least 10 kg, it is used to treat venous thromboembolism (VTE).

See full Fondaparinux Injection drug information
Keep checking

Other Drugs & Fulvic Acid

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

0Major
256Moderate
0Minor
2,573No known interaction
Moderate

256 interactions

Showing 60 of 256 moderate interactions — see all 256 on the Fulvic Acid page.

No interaction 2,573 drugs checked — show the list

We also checked Fulvic Acid against these medications and found no known interaction in our sources. Open any page to confirm.

Showing the 60 most looked-up of 2,573 medications checked with no known interaction — see the full Fulvic Acid 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 Fulvic Acid and Fondaparinux Together: Common Questions

Can you take Fulvic Acid 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 Fulvic Acid 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

Still Have a Question About Fondaparinux and Fulvic Acid?

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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.