Drug & supplement interaction

Hemp + Fondaparinux

Fondaparinux brand name: Arixtra.

Minor Interaction
The bottom line Minor

Hemp has a minor interaction with Fondaparinux. Theoretically, hemp seed might increase the risk of bleeding when used concomitantly with anticoagulant/antiplatelet drugs.

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

Hemp and Fondaparinux

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

Minor

ANTICOAGULANT/ANTIPLATELET DRUGS

Why this applies to Fondaparinux

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

Theoretically, hemp seed might increase the risk of bleeding when used concomitantly with anticoagulant/antiplatelet drugs.
In animal research, hemp seed at 5% of the diet inhibits platelet aggregation in vitro. However, in human research, taking hemp seed oil 2 grams daily for 12 weeks does not inhibit the aggregation of platelets in vitro.
Severity Minor 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 bottom line on pairing hemp with fondaparinux (Arixtra). Fondaparinux is a strong blood thinner that blocks a clotting factor called factor Xa. The concern is that hemp might add to its blood-thinning effect, so in theory you could bruise or bleed a bit more easily.

That said, the evidence here is very thin. The idea comes from lab and animal studies where hemp slowed platelet clumping, but a human study using hemp seed oil showed no real effect on platelets. So everyday hemp seeds or oil in food are unlikely to cause a problem. Since fondaparinux is a serious injectable medication, it's still smart to mention any hemp supplements to your pharmacist or doctor, and watch for unusual bruising, nosebleeds, or bleeding gums.

References
  1. Kaul N, Kreml R, Austria JA, et al. A comparison of fish oil, flaxseed oil and hempseed oil supplementation on selected parameters of cardiovascular health in healthy volunteers. J Am Coll Nutr 2008;27:51-8. PubMed
  2. Richard MN, Ganguly R, Steigerwald SN, Al-Khalifa A, Pierce GN. Dietary hempseed reduces platelet aggregation. J Thromb Haemost. 2007;5(2):424-5. 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

Hemp Also Interacts With Other Medications

Hemp has 41 moderate, 896 minor 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 Hemp

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

Everything else you take

See Every Supplement That Interacts With Fondaparinux

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

We hold 720 real supplement products containing Hemp, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Hemp. Your product may carry other ingredients that interact with Fondaparinux too, on top of Hemp — 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 Hemp 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 Hemp
Top 25%

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

29 days ago today
Medication Fondaparinux
Top half

#907 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 Hemp

What is Hemp?

Hemp
  • Plant-based protein source
  • Heart health support
  • Skin and hair health
  • Reducing inflammation
  • General nutrition (omega fatty acids)

Hemp seeds and hemp seed oil are nutritious foods rich in protein, fiber, and healthy omega-3 and omega-6 fatty acids, and they are generally safe for most people as part of the diet. While the nutrition is real, strong human evidence that hemp supplements treat specific medical conditions is limited. Talk with your pharmacist or doctor before using hemp products for a health concern, especially if you are pregnant or breastfeeding.

Read the full Hemp 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. For hip fracture patients, an extended course of prevention is recommended after the initial treatment period.

It is also used to treat an existing DVT or acute pulmonary embolism (PE — a clot in the lungs) in adults, always given alongside warfarin sodium until warfarin reaches a therapeutic level. In pediatric patients aged 1 year and older who weigh at least 10 kg, fondaparinux sodium injection is approved for the treatment of venous thromboembolism (VTE — blood clots in the veins).

See full Fondaparinux Injection drug information
Keep checking

Other Drugs & Hemp

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

0Major
41Moderate
896Minor
1,892No known interaction
Moderate

41 interactions

Minor

896 interactions

Showing 60 of 896 minor interactions — see all 896 on the Hemp page.

No interaction 1,892 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 Hemp and Fondaparinux Together: Common Questions

Can you take Hemp with Fondaparinux?
There is only a minor interaction, which is usually not serious. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Hemp and Fondaparinux interaction?
We rate it Minor. This interaction is generally not clinically significant, but it remains worth noting and discussing with your pharmacist.

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

Still Have a Question About Fondaparinux and Hemp?

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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.