Drug & supplement interaction

Flaxseed Oil + Diclofenac

Diclofenac brand name: Zorvolex.

Moderate Interaction
The bottom line Moderate

Flaxseed Oil has a moderate interaction with Diclofenac. Theoretically, using flaxseed oil in combination with anticoagulant or antiplatelet drugs might have additive effects and increase the risk of bleeding.

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

Flaxseed Oil and Diclofenac

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

Moderate

ANTICOAGULANT/ANTIPLATELET DRUGS

Why this applies to Diclofenac

Diclofenac falls under ANTICOAGULANT/ANTIPLATELET DRUGS — the group Flaxseed Oil interacts with.

Theoretically, using flaxseed oil in combination with anticoagulant or antiplatelet drugs might have additive effects and increase the risk of bleeding.
Small clinical studies show that consuming flaxseed oil might decrease platelet aggregation and increase bleeding time.
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 gist with diclofenac and flaxseed oil. Diclofenac is an NSAID, and one of its known downsides is that it can make your blood a little slower to clot and can irritate the stomach lining. Flaxseed oil, in some small studies, seems to nudge platelets toward sticking together less, which can lengthen bleeding time too. Put them together and those effects may stack.

I'll be honest: this concern is mostly theoretical and based on how these two work, not on strong human trials. For most people it's a minor issue, but if you bruise easily, take other blood thinners, or notice dark stools or nosebleeds, check in with your pharmacist or doctor before combining them.

References
  1. Nordstrom DC, Honkanen VE, Nasu Y, et al. Alpha-linolenic acid in the treatment of rheumatoid arthritis. A double-blind, placebo-controlled and randomized study: flaxseed vs. safflower seed. Rheumatol Int 1995;14:231-4. PubMed
  2. Allman, M. A., Pena, M. M., and Pang, D. Supplementation with flaxseed oil versus sunflowerseed oil in healthy young men consuming a low fat diet: effects on platelet composition and function. Eur.J Clin.Nutr. 1995;49(3):169-178.

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

Flaxseed Oil Also Interacts With Other Medications

Flaxseed Oil has 292 moderate known drug interactions in our database — the Diclofenac 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 Flaxseed Oil

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

From our Q&A

Questions About Flaxseed Oil or Diclofenac

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

This page covers Flaxseed Oil only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Diclofenac page lists 306 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Asarabacca (major), Beer (major), Danshen (major) and Piracetam (major).

By severity: 7 major · 265 moderate · 34 minor.

From our pharmacist’s overview on the Diclofenac page

“Diclofenac (Zorvolex) is an NSAID pain reliever that already stresses the stomach lining and kidneys on its own, so treat this list as a real safety issue, not fine print. Two thirds of the 306 supplements on file can thin the blood or slow clotting, and stacked on an NSAID that raises the odds of stomach bleeding.”

Reviewed by 2 · Jul 18, 2026

Open the Diclofenac interaction page

One more smart check

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

We hold 1,329 real supplement products containing Flaxseed Oil, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Flaxseed Oil. Your product may carry other ingredients that interact with Diclofenac too, on top of Flaxseed Oil — 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 Flaxseed Oil and Diclofenac 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 Flaxseed Oil
Top 25%

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

29 days ago today
Medication Diclofenac
Top 10%

#242 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 Flaxseed Oil

What is Flaxseed Oil?

  • Source of omega-3 (ALA) fatty acids
  • Heart and cholesterol health
  • Dry skin and inflammation
  • Constipation
  • General wellness

Flaxseed oil is a plant-based source of the omega-3 fatty acid ALA, which the body can partly convert to the omega-3s found in fish oil. It may help support heart health and provide healthy fats, but evidence for most specific health claims is limited or mixed. It is generally well tolerated, but talk to your pharmacist or doctor before starting, especially if you are pregnant or have a bleeding risk.

Read the full Flaxseed Oil monograph & all interactions
Medication

About Diclofenac

What Is Diclofenac Used For?

Brand name: Zorvolex

Diclofenac sodium topical gel is used to treat actinic keratoses (AK) — rough, scaly skin patches that form after years of sun exposure. These patches are considered precancerous, meaning they can develop into skin cancer if left untreated.

This is a topical gel, meaning it is applied directly to the skin over the affected area rather than taken by mouth. It belongs to the NSAID (nonsteroidal anti-inflammatory drug) family.

See full Diclofenac drug information
Keep checking

Other Drugs & Flaxseed Oil

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

0Major
292Moderate
0Minor
2,537No known interaction
Moderate

292 interactions

Showing 60 of 292 moderate interactions — see all 292 on the Flaxseed Oil page.

No interaction 2,537 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 Flaxseed Oil and Diclofenac Together: Common Questions

Can you take Flaxseed Oil with Diclofenac?
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 Flaxseed Oil and Diclofenac 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 Diclofenac and Flaxseed Oil?

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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.