Drug & supplement interaction

Blue Cohosh + Nadolol

Nadolol brand names: Corgard, Nadolol.

Moderate Interaction
The bottom line Moderate

Blue Cohosh has a moderate interaction with Nadolol. Constituents in blue cohosh might increase blood pressure by causing coronary vasoconstriction.

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

Blue Cohosh and Nadolol

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

Moderate

ANTIHYPERTENSIVE DRUGS

Why this applies to Nadolol

Nadolol falls under ANTIHYPERTENSIVE DRUGS — the group Blue Cohosh interacts with.

Constituents in blue cohosh might increase blood pressure by causing coronary vasoconstriction. Theoretically, concomitant use might decrease the effectiveness of drugs used for angina and high blood pressure; use with caution. Some antihypertensive drugs include captopril (Capoten), enalapril (Vasotec), losartan (Cozaar), valsartan (Diovan), diltiazem (Cardizem), Amlodipine (Norvasc), hydrochlorothiazide (HydroDiuril), furosemide (Lasix), and many 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

Here's the concern with pairing blue cohosh and nadolol. Some compounds in blue cohosh may tighten or narrow blood vessels, which can nudge your blood pressure up and tighten the vessels around your heart. Since you take nadolol to relax those vessels, slow your heart, and ease chest pain, the herb could work against it. In plain terms, it might blunt some of the benefit, so your blood pressure or angina could be harder to control.

To be fair, this is a theoretical worry based on how the plant behaves, not strong human studies. Still, blue cohosh has real safety concerns of its own, so I'd skip it and check with your pharmacist or doctor before using it alongside nadolol.

References
  1. Fetrow CW, Avila JR. Professional's Handbook of Complementary & Alternative Medicines. 1st ed. Springhouse, PA: Springhouse Corp., 1999.

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

Blue Cohosh Also Interacts With Other Medications

Blue Cohosh has 258 moderate known drug interactions in our database — the Nadolol 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 Blue Cohosh

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

Everything else you take

See Every Supplement That Interacts With Nadolol

This page covers Blue Cohosh 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

One more smart check

Taking Blue Cohosh as Part of a Dietary Supplement Product? Check It for Interactions

We hold 126 real supplement products containing Blue Cohosh, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Blue Cohosh. Your product may carry other ingredients that interact with Nadolol too, on top of Blue Cohosh — 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 Blue Cohosh 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 Blue Cohosh
Steady interest

#1,098 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Nadolol
Top half

#1,018 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 Blue Cohosh

What is Blue Cohosh?

  • Inducing labor or starting menstruation
  • Menstrual cramps and irregular periods
  • Symptoms of menopause
  • Pelvic or uterine discomfort
  • Traditional Native American remedy

Blue cohosh is a traditional herb historically used by Native Americans and midwives to bring on labor or menstruation, but it carries serious safety concerns, especially for the heart and during pregnancy. There is very little reliable human evidence that it works, and reports of harm—including serious problems in newborns—make it an herb most people should avoid without close professional supervision.

Read the full Blue Cohosh 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.

See full Nadolol drug information
Keep checking

Other Drugs & Blue Cohosh

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

0Major
258Moderate
0Minor
2,571No known interaction
Moderate

258 interactions

Showing 60 of 258 moderate interactions — see all 258 on the Blue Cohosh page.

No interaction 2,571 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 Blue Cohosh and Nadolol Together: Common Questions

Can you take Blue Cohosh with Nadolol?
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 Blue Cohosh and Nadolol 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 Nadolol and Blue Cohosh?

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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.