Drug & supplement interaction

Celery + Timolol

Timolol brand names: Blocadren, Timol, Timoptic.

Moderate Interaction
The bottom line Moderate

Celery has a moderate interaction with Timolol. Theoretically, celery seed extract might have additive effects with antihypertensive drugs.

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

Celery and Timolol

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

Moderate

ANTIHYPERTENSIVE DRUGS

Why this applies to Timolol

Timolol falls under ANTIHYPERTENSIVE DRUGS — the group Celery interacts with.

Theoretically, celery seed extract might have additive effects with antihypertensive drugs.
Clinical research suggests that taking celery seed extract may reduce daytime systolic blood pressure by about 12 mmHg compared to less than 1 mmHg with placebo.
Severity Moderate Likelihood Probable Evidence B

Interaction 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..

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

Here's the simple version: celery seed extract may gently lower blood pressure on its own, and timolol (when taken as a pill or used as eye drops) already works to relax your blood vessels and slow your heart rate. Stacking the two can have an additive effect, meaning your numbers could drop more than expected.

If that happens, you might feel lightheaded, dizzy, unusually tired, or notice your pulse running slow, especially when standing up quickly. This is based on a lower quality study where concentrated celery seed extract dropped daytime blood pressure by around 12 mmHg, so supplement doses matter much more than eating celery in your meals. Celery as food is unlikely to be a problem. Before starting a celery supplement, check with your pharmacist or doctor so they can keep an eye on your blood pressure.

References
  1. Shayani Rad M, Moohebati M, Mohajeri SA. Effect of celery (Apium graveolens) seed extract on hypertension: A randomized, triple-blind, placebo-controlled, cross-over, clinical trial. Phytother Res 2022.

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

Celery Also Interacts With Other Medications

Celery has 448 moderate, 202 minor known drug interactions in our database — the Timolol 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 Celery

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

From our Q&A

Questions About Celery or Timolol

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

This page covers Celery only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Timolol page lists 183 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), Indian Snakeroot (major) and Tyramine (major).

By severity: 5 major · 151 moderate · 27 minor.

From our pharmacist’s overview on the Timolol page

“The supplement list for timolol (Blocadren, Timoptic) calls for genuine care, starting with its five major-rated entries. Timolol is a beta-blocker that slows the heart and lowers blood pressure, and even the eye-drop form absorbs enough to matter.”

Reviewed by 2 · Jul 18, 2026

Open the Timolol interaction page

One more smart check

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

We hold 1,687 real supplement products containing Celery, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Celery. Your product may carry other ingredients that interact with Timolol too, on top of Celery — 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 Celery and Timolol 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 Celery
Top 25%

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

29 days ago today
Medication Timolol
Steady interest

#1,608 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 Celery

What is Celery?

Celery
  • High blood pressure
  • Fluid retention (diuretic)
  • Joint pain and inflammation
  • Anxiety and sleep
  • Digestive support

Celery is a common vegetable that is also taken as a seed extract or oil supplement, mainly for blood pressure, fluid retention, and joint discomfort. Human evidence for these supplement uses is limited and mostly preliminary, so it should not replace proven treatments. Celery is generally safe as food, but concentrated supplements and possible allergic reactions warrant caution.

Read the full Celery monograph & all interactions
Medication

About Timolol

What Is Timolol Used For?

Brand names: Blocadren, Timol, Timoptic

Timolol eye drops lower raised pressure inside the eye in people with ocular hypertension or open-angle glaucoma. This is the use for every eye product listed, including Timoptic, Timoptic-XE, Istalol, Betimol and Timolol GFS.

Timolol Maleate tablets (taken by mouth) have different uses. They treat high blood pressure, reduce the risk of death and repeat heart attack in stable patients who have survived the acute phase of a heart attack, and help prevent migraine headaches.

See full Timolol drug information
Keep checking

Other Drugs & Celery

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

0Major
448Moderate
202Minor
2,179No known interaction
Moderate

448 interactions

Showing 60 of 448 moderate interactions — see all 448 on the Celery page.

Minor

202 interactions

Showing 60 of 202 minor interactions — see all 202 on the Celery page.

No interaction 2,179 drugs checked — show the list

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

Showing the 60 most looked-up of 2,179 medications checked with no known interaction — see the full Celery 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 Celery and Timolol Together: Common Questions

Can you take Celery with Timolol?
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 Celery and Timolol 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 Timolol and Celery?

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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.