Drug & supplement interaction

Canadian Fleabane + Dicumarol

Dicumarol brand name: Dicumarol.

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

Canadian Fleabane has a moderate interaction with Dicumarol. Theoretically, Canadian fleabane might cause additive effects and side effects when used with anticoagulant or antiplatelet drugs.

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

Canadian Fleabane and Dicumarol

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

Moderate

ANTICOAGULANT/ANTIPLATELET DRUGS

Why this applies to Dicumarol

Dicumarol falls under ANTICOAGULANT/ANTIPLATELET DRUGS — the group Canadian Fleabane interacts with.

Theoretically, Canadian fleabane might cause additive effects and side effects when used with anticoagulant or antiplatelet drugs. Canadian fleabane has been shown to inhibit platelet aggregation in vitro.
Some anticoagulant/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

Dicumarol is a blood thinner that works a lot like warfarin, slowing your body's ability to form clots. The concern here is simple addition: Canadian fleabane has shown some ability to slow platelets from clumping together in lab studies, so stacking it on top of dicumarol could, in theory, push your blood-thinning a little too far. That might show up as easy bruising, nosebleeds, bleeding gums, or harder-to-stop cuts.

I want to be honest that this is theoretical and based on test-tube data, not real patient studies. Still, dicumarol is a drug where small shifts matter, so I'd play it safe. Don't start or stop anything on your own, just loop in your doctor or pharmacist before adding fleabane.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Saluk-Juszczak J, Olas B, Pawlaczyk I, Gancarz R, Wachowicz B. Effects of the extract from Conyza canadensis on human blood platelet aggregation. Gen Physiol Biophys 2007;26(2):150-2.
  2. Olas B, Saluk-Juszczak J, Pawlaczyk I, et al. Antioxidant and antiaggregatory effects of an extract from Conyza canadensis on blood platelets in vitro. Platelets 2006;17(6):354-60.

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

Canadian Fleabane Also Interacts With Other Medications

Canadian Fleabane has 121 moderate known drug interactions in our database — the Dicumarol one above is one of them. If you take anything else, check it against the full list below.

Moderate 121 No known interaction 2,709 (incl. Dicumarol)
Taking anything else?

Check Another of Your Medications Against Canadian Fleabane

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

Everything else you take

See Every Supplement That Interacts With Dicumarol

This page covers Canadian Fleabane only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Dicumarol page lists 218 supplements it has a documented interaction with, worst first, each one explained.

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

By severity: 3 major · 190 moderate · 25 minor.

From our pharmacist’s overview on the Dicumarol page

“Danshen tops my worry list for anyone taking dicumarol, an older blood thinner in the warfarin family. It has clot-blocking activity of its own, and stacking it on an anticoagulant can push bleeding risk too far.”

Reviewed by 2 · Jul 18, 2026

Open the Dicumarol interaction page

How much people look this up

Where Canadian Fleabane and Dicumarol 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 Canadian Fleabane
Steady interest

#1,099 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Dicumarol
Steady interest

#2,155 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 Canadian Fleabane

What is Canadian Fleabane?

  • Diarrhea
  • Minor bleeding
  • Urinary complaints
  • Digestive upset
  • Sore throat and inflammation

Canadian Fleabane is a common North American weed used in traditional medicine for diarrhea, minor bleeding, and urinary issues, but high-quality human studies are lacking. Because its safety has not been well studied, it is best to talk with your pharmacist or doctor before using it, and to avoid it during pregnancy and breastfeeding.

Read the full Canadian Fleabane monograph & all interactions
Keep checking

Other Drugs & Canadian Fleabane

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

0Major
121Moderate
0Minor
2,708No known interaction
121 Moderate 2,708 No interaction
Moderate

121 interactions

Showing 60 of 121 moderate interactions — see all 121 on the Canadian Fleabane page.

No interaction 2,708 drugs checked — show the list

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

Showing the 60 most looked-up of 2,708 medications checked with no known interaction — see the full Canadian Fleabane list.

See the full Canadian Fleabane interactions page
See every supplement checked against Dicumarol, 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
Canadian Fleabane monograph › Uses, safety, and every drug interaction in one place Dicumarol supplement interactions › Every supplement checked against Dicumarol, ranked by severity 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 Canadian Fleabane and Dicumarol Together: Common Questions

Can you take Canadian Fleabane with Dicumarol?
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 Canadian Fleabane and Dicumarol 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 Dicumarol and Canadian Fleabane?

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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.