Drug & supplement interaction

Canadian Fleabane + Nadolol

Nadolol brand names: Corgard, Nadolol.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Canadian Fleabane and Nadolol 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 Nadolol

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 Nadolol 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 Nadolol and Canadian Fleabane? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Nadolol

Interactions in our licensed database are recorded against drug classes, not just single drug names. Nadolol is filed under 5 classifications — including beta-blockers, antihypertensive drugs, seizure threshold lowering drugs. Canadian Fleabane has documented interactions with 1 drug class — the most serious being anticoagulant/antiplatelet drugs (moderate) — and none of Nadolol’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 — Nadolol 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 Nadolol’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 Nadolol’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. 10 of them are worth acting on rather than waiting out — marked below.

  • Memory problems Worth acting on
  • A slow heartbeat Worth acting on
  • Blood clots Worth acting on
  • Hallucinations Worth acting on
  • Heart failure Worth acting on
  • Wheezing Worth acting on
  • Confusion Worth acting on
  • Low mood Worth acting on
  • Shortness of breath Worth acting on
  • A low white blood cell count Worth acting on

Showing the 10 most notable of 41 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 Nadolol. Read the label on DailyMed › Where a percentage is shown, it is the share of 7,530 voluntary FDA FAERS reports for Nadolol that mention that effect — a reporting proportion, not an incidence rate and not evidence the drug caused it. 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.

Everything else you take

See Every Supplement That Interacts With Nadolol

This page covers Canadian Fleabane only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Nadolol page lists 145 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), Green Tea (major) and Indian Snakeroot (major).

By severity: 6 major · 119 moderate · 20 minor.

From our pharmacist’s overview on the Nadolol page

“If you take nadolol (Corgard) for blood pressure, angina, or heart rhythm, treat this list with real care, and green tea is the surprise at the top. In a clinical study, green tea cut nadolol blood levels by roughly 85 percent, which can quietly leave you undertreated.”

Reviewed by 2 · Jul 18, 2026

Open the Nadolol interaction page

How much people look this up

Where Canadian Fleabane and Nadolol 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

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

29 days ago today
Medication Nadolol
Steady interest

#1,682 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 Nadolol 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 Nadolol

What Is Nadolol Used For?

Brand names: Corgard, Nadolol

Nadolol tablets are used for two main conditions: high blood pressure (hypertension) and angina pectoris (ongoing chest pain caused by reduced blood flow to the heart). Lowering high blood pressure reduces the risk of stroke and heart attack.

For high blood pressure, nadolol may be prescribed on its own or combined with other blood pressure medications, especially thiazide-type diuretics (water pills). For angina, it is used for long-term management to help reduce how often chest pain occurs.

Most-Reported Side Effects for Nadolol

From FAERS, the FDA’s public side-effect reporting system (7,530 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Macular degeneration 831 reports
Nausea 673 reports
Headache 603 reports
Fatigue 526 reports
Weight decreased 464 reports
See full Nadolol 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 Nadolol Together: Common Questions

Is it safe to take Canadian Fleabane with Nadolol?
We do not list a known interaction between Canadian Fleabane and Nadolol. 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 Nadolol combination checked?
Interactions in our licensed database are recorded against drug classes. Nadolol is filed under 5 classifications, and Canadian Fleabane has documented interactions with 1 drug class — none of Nadolol'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 — Nadolol 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 Nadolol interact with any supplements?
Yes. Nadolol has documented interactions with 145 supplements in our database — Canadian Fleabane is not one of them. The Nadolol 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 Nadolol 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.