Drug & supplement interaction

Canadian Fleabane + Verapamil

Verapamil brand names: Isoptin SR, Verelan, Isoptin, Calan SR, Verelan SR, and others.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Canadian Fleabane and Verapamil in our sources. Absence of a documented interaction is not the same as proven safety, and does not guarantee one does not exist. Do not start, stop, or change a medication or supplement based on this page; confirm with your pharmacist or doctor first.

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Interaction report

Canadian Fleabane and Verapamil

We checked these two against our interaction database. Here is what we found.

No Known Interaction Found

We did not find a documented interaction between Verapamil and Canadian Fleabane in our sources. This does not guarantee that the combination is completely free of risk — there is often limited research on supplements and herbal products, especially around drug interactions.

If you decide to take both, the practical routine is simple: add one new thing at a time and note the date you started it. If the combination is going to disagree with you, it usually shows in the first days to a couple of weeks — and a start date turns “I’ve been feeling off” into something a pharmacist can actually work with. Do not stop a prescribed medicine on your own.

Always talk with your pharmacist or doctor before making changes to your medications or supplements, particularly if you take several medications or have an ongoing health condition.

Canadian Fleabane safety at a glance

Canadian Fleabane overall Use caution Used traditionally, but human safety data are limited so use cautiously.
Pregnancy Avoid Not enough safety information, so avoid use during pregnancy.
Breastfeeding Avoid Not enough safety information, so avoid use while breastfeeding.

Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Verapamil and Canadian Fleabane? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Verapamil

Interactions in our licensed database are recorded against drug classes, not just single drug names. Verapamil is filed under 11 classifications — including calcium channel blockers, cytochrome p450 2c8 (cyp2c8) substrates, cytochrome p450 3a4 (cyp3a4) inhibitors. Canadian Fleabane has documented interactions with 1 drug class — the most serious being anticoagulant/antiplatelet drugs (moderate) — and none of Verapamil’s classifications are among them.

Classification data comes from our licensed Natural Medicines dataset. A medication can belong to classes beyond those recorded there, so this describes how the check was run — it is not a safety guarantee.

Keep it in perspective

Canadian Fleabane Does Interact With Other Medications

Canadian Fleabane has 122 moderate known drug interactions in our database — Verapamil isn’t one of them. If you take anything else, check it against the full list below.

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.

What to actually watch for

What Verapamil’s Own FDA Label Lists

This is not an interaction — none of it involves Canadian Fleabane. These are the most notable effects listed in the ADVERSE REACTIONS section of Verapamil’s own FDA label, for the medication by itself. Knowing the drug’s own list makes it easier to work out the likely cause if something new turns up while you take both. 6 of them are worth acting on rather than waiting out — marked below.

  • A bowel blockage Worth acting on
  • A slow heartbeat Worth acting on
  • Heart failure Worth acting on
  • Raised blood pressure Worth acting on
  • Liver problems Worth acting on
  • A higher chance of infection Worth acting on
  • A stuffy or runny nose
  • Sore throat
  • Low blood pressure
  • Stomach upset

Showing the 10 most notable of 17 label-listed effects — ranked by how unusual each one is across medicines generally, with serious effects weighted up.

From the ADVERSE REACTIONS section of the FDA label for Verapamil. Read the label on DailyMed › Canadian Fleabane’s licensed record lists no adverse effects our clinical vocabulary could match, so there is no Canadian Fleabane side to compare — that is a limit of the record, not a statement that Canadian Fleabane has no side effects.

From our Q&A

Questions About Canadian Fleabane or Verapamil

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Canadian Fleabane or Verapamil, 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 Verapamil

This page covers Canadian Fleabane only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Verapamil page lists 295 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), American Hellebore (major), American Mistletoe (major), Beer (major) and Coleus (major).

By severity: 10 major · 245 moderate · 40 minor.

From our pharmacist’s overview on the Verapamil page

“This is one of the longer interaction lists we publish, and with verapamil (Calan, Verelan) it warrants genuine care, starting with the ten major-rated entries. Verapamil lowers blood pressure and slows the heart, so most of the 295 ingredients on file either push that effect further than intended or change how much of the drug reaches…”

Reviewed by 2 · Jul 18, 2026

Open the Verapamil interaction page

How much people look this up

Where Canadian Fleabane and Verapamil 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
Top half

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

29 days ago today
Medication Verapamil
Top 10%

#200 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.

Where does our data come from?
  • Source: the Natural Medicines (TRC Healthcare) clinical database — the evidence-graded professional reference for herb & supplement interactions.
  • Citation library: 103,510 references behind our interaction content, 65,311 of them resolved to verified PubMed/DOI sources. See every Canadian Fleabane reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 20, 2026. The Canadian Fleabane and Verapamil records this page draws on were last updated June 22, 2026.
  • What “no known interaction” means: no documented interaction in the sources above — not a guarantee of safety. Supplements are studied far less than prescription drugs, so we say exactly what the evidence supports, and nothing more.
Data structure & sourcing designed and verified by .
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.

Erigeron canadensis · Asteraceae · Aerial parts (leaves, stems, flowers) and the essential oil · Tea, tincture, dried herb, liquid extract, essential oil

An interaction check asks whether these two react with each other — it does not ask whether Canadian Fleabane is a good idea for someone in your situation. Here is what our Canadian Fleabane record says about it on its own.

Canadian Fleabane: dosing

There is no established, science-based standard dose for Canadian Fleabane. Traditional preparations such as teas and tinctures vary widely in strength, and product labels differ from brand to brand.If you choose to use a commercial product, follow the directions on the label and do not exceed them. The essential oil is very concentrated and is not meant to be taken by mouth without professional guidance.

From our Canadian Fleabane monograph — the full record covers uses, side effects and every documented interaction.

Read the full Canadian Fleabane monograph & all interactions
Medication

About Verapamil

What Is Verapamil Used For?

Brand names: Isoptin SR, Verelan, Isoptin, Calan SR, Verelan SR, Calan, Covera HS, Verap, Veramil

Verapamil tablets and film-coated tablets are used to treat angina — including vasospastic (Prinzmetal's) angina, unstable angina, and chronic stable angina — as well as certain abnormal heart rhythms (arrhythmias) and high blood pressure (essential hypertension). For arrhythmias, regular-release tablets are used alongside digoxin to control heart rate in atrial flutter or atrial fibrillation, and to help prevent episodes of paroxysmal supraventricular tachycardia (SVT), a type of rapid heartbeat.

Extended-release and sustained-release oral forms (tablets and capsules) are indicated specifically for high blood pressure. Verapamil hydrochloride injection is used in hospital settings for rapid conversion of SVT to normal rhythm and for temporary control of fast heart rates in atrial flutter or atrial fibrillation.

Most-Reported Side Effects for Verapamil

From FAERS, the FDA’s public side-effect reporting system (4,297 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Dyspnea 352 reports
Nausea 351 reports
Dizziness 295 reports
Hypotension 293 reports
Fatigue 275 reports
See full Verapamil drug information
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
122Moderate
0Minor
2,707No known interaction
Moderate

122 interactions

Showing 60 of 122 moderate interactions — see all 122 on the Canadian Fleabane page.

No interaction 2,707 drugs checked — show the list
Evidence & sources

Canadian Fleabane References

The 2 references that drive our Canadian Fleabane monograph and interaction data, from the evidence-graded Natural Medicines (TRC Healthcare) database. Citations with a link open the study on PubMed or the publisher’s site.

  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.

Medication overviews come from MedlinePlus (NIH); supplement label data from the NIH Dietary Supplement Label Database. Content is written and reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.

Pharmacist Counseling Corner

Taking Canadian Fleabane and Verapamil Together: Common Questions

Is it safe to take Canadian Fleabane with Verapamil?
We do not list a known interaction between Canadian Fleabane and Verapamil. That does not guarantee the combination is risk-free, so confirm with your pharmacist or doctor — especially if you take other medications or have a health condition.
How was the Canadian Fleabane and Verapamil combination checked?
Interactions in our licensed database are recorded against drug classes. Verapamil is filed under 11 classifications, and Canadian Fleabane has documented interactions with 1 drug class — none of Verapamil's classifications are among them. A medication can belong to classes beyond those recorded in our dataset, so this describes how the check was run rather than guaranteeing safety.
Does Canadian Fleabane interact with any other medications?
Yes. Canadian Fleabane has 122 documented drug interactions in our database — Verapamil is simply not one of them. If you take anything else, it is worth checking each one; they are all listed on this page.
Does Verapamil interact with any supplements?
Yes. Verapamil has documented interactions with 295 supplements in our database — Canadian Fleabane is not one of them. The Verapamil interaction page linked on this page lists every one, ranked by severity.

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

Still Have a Question About Verapamil 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.