Drug & supplement interaction

Basil + Bendroflumethiazide, Nadolol

Bendroflumethiazide, Nadolol brand name: Corzide.

Moderate Interaction
The bottom line Moderate

Basil has a moderate interaction with Bendroflumethiazide, Nadolol. Theoretically, basil might increase the risk of hypotension when taken with antihypertensive drugs.

Read the full interaction report
SeverityModerate
LikelihoodPossible
EvidenceD
What do Severity, Likelihood & Evidence mean?
Know someone taking this? Share
Interaction report

Basil and Bendroflumethiazide, Nadolol

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

Moderate

ANTIHYPERTENSIVE DRUGS

Why this applies to Bendroflumethiazide, Nadolol

Bendroflumethiazide, Nadolol falls under ANTIHYPERTENSIVE DRUGS — the group Basil interacts with.

Theoretically, basil might increase the risk of hypotension when taken with antihypertensive drugs.
Animal research suggests that basil extract can reduce systolic and diastolic blood pressure.
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

Corzide combines two blood pressure medicines: nadolol (a beta blocker) and bendroflumethiazide (a water pill). Both already work to lower your blood pressure. The concern here is simple: concentrated basil supplements or basil essential oil might add a little extra blood-pressure-lowering effect on top of your medication.

I want to be honest about how thin this evidence is. It comes only from animal studies, not human trials, so it's largely theoretical. Using basil as a cooking herb in normal food amounts is not a worry. If you take strong basil supplements, just watch for signs your pressure dipped too low: dizziness, lightheadedness when you stand, or feeling unusually tired. Check with your pharmacist or doctor before starting any concentrated basil product.

References
  1. Umar, A., Imam, G., Yimin, W., Kerim, P., Tohti, I., Berke, B., and Moore, N. Antihypertensive effects of Ocimum basilicum L. (OBL) on blood pressure in renovascular hypertensive rats. Hypertens.Res 5-7-2010; 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

Basil Also Interacts With Other Medications

Basil has 288 moderate known drug interactions in our database — the Bendroflumethiazide, 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 Basil

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

From our Q&A

Questions About Basil or Bendroflumethiazide, Nadolol

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

This page covers Basil only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Bendroflumethiazide, Nadolol page lists 235 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), Asarabacca (major) and Dolomite (major).

By severity: 12 major · 199 moderate · 24 minor.

From our pharmacist’s overview on the Bendroflumethiazide, Nadolol page

“Green tea worries me most. In human studies it cut blood levels of nadolol by roughly 85 percent, enough to undermine Corzide (bendroflumethiazide with nadolol) as a blood pressure treatment, and it earns one of the 12 major ratings here.”

Reviewed by 2 · Jul 18, 2026

Open the Bendroflumethiazide, Nadolol interaction page

One more smart check

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

We hold 396 real supplement products containing Basil, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Basil. Your product may carry other ingredients that interact with Bendroflumethiazide, Nadolol too, on top of Basil — 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 Basil and Bendroflumethiazide, 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 Basil
Top 25%

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

29 days ago today
Medication Bendroflumethiazide, Nadolol
Steady interest

#1,989 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 Basil

What is Basil?

Basil
  • Digestive upset and gas
  • Stress and anxiety
  • Antimicrobial support
  • Cold and cough symptoms
  • Headache
  • General antioxidant support

Basil is a popular cooking herb that is generally safe in the amounts used in food. While it has a long history of traditional medicinal use and contains antioxidant compounds, strong human evidence for most health claims is limited. Talk with your pharmacist or doctor before using concentrated supplements or essential oils.

Read the full Basil monograph & all interactions
Keep checking

Other Drugs & Basil

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

0Major
288Moderate
0Minor
2,541No known interaction
Moderate

288 interactions

Showing 60 of 288 moderate interactions — see all 288 on the Basil page.

No interaction 2,541 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

Keep exploring
Pharmacist Counseling Corner

Taking Basil and Bendroflumethiazide, Nadolol Together: Common Questions

Can you take Basil with Bendroflumethiazide, 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 Basil and Bendroflumethiazide, 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 Bendroflumethiazide, Nadolol and Basil?

Our pharmacists answer your medication & supplement questions — free.

Ask a pharmacist

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.