Drug & supplement interaction

Flaxseed Oil + simvastatin/ezetimibe

simvastatin/ezetimibe brand name: Vytorin.

Moderate Interaction
Medically reviewed by · Updated September 2026
The bottom line Moderate

Flaxseed Oil has a moderate interaction with simvastatin/ezetimibe. Concomitant use of flaxseed oil and ezetimibe reduces the absorption of alpha-linolenic acid from flaxseed oil.

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

Flaxseed Oil and simvastatin/ezetimibe

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

Moderate

EZETIMIBE (Zetia)

Concomitant use of flaxseed oil and ezetimibe reduces the absorption of alpha-linolenic acid from flaxseed oil.
In one clinical study, concomitant consumption of ezetimibe 10 mg daily with flaxseed oil 2 grams providing 1 gram of alpha-linolenic acid daily blocked the absorption of alpha-linolenic acid, resulting in an overall reduction in alpha-linolenic plasma levels from baseline.
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 a twist that surprises a lot of people: this interaction works the other way around. The ezetimibe portion of your Vytorin blocks cholesterol absorption in your gut, and in one clinical study it also blocked the absorption of the healthy omega-3 (alpha-linolenic acid) from flaxseed oil. So taking them together doesn't make your medication stronger or more dangerous. Instead, you may simply get less benefit from the flaxseed oil itself, since your body absorbs less of its active ingredient.

The good news is your simvastatin/ezetimibe still works as expected for lowering cholesterol. If you're taking flaxseed oil for a real reason, it just may not deliver as much. Chat with your pharmacist about whether it's worth continuing or spacing apart.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Blackwood DP, LaVallee RK, Al Busaidi A, Jassal DS, Pierce GN. A randomized trial of the effects of ezetimibe on the absorption of omega-3 fatty acids in cardiac disease patients: a pilot study. Clin Nutr ESPEN. 2015 Oct;10(5):e155-e159. 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

Flaxseed Oil Also Interacts With Other Medications

Flaxseed Oil has 292 moderate known drug interactions in our database — the simvastatin/ezetimibe one above is one of them. If you take anything else, check it against the full list below.

Moderate 292 No known interaction 2,538 (incl. simvastatin/ezetimibe)
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.

Everything else you take

See Every Supplement That Interacts With simvastatin/ezetimibe

This page covers Flaxseed Oil only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the simvastatin/ezetimibe page lists 184 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Apple (major), Beer (major), Grapefruit (major) and Siberian Cocklebur (major).

By severity: 8 major · 140 moderate · 36 minor.

From our pharmacist’s overview on the simvastatin/ezetimibe page

“Anyone taking simvastatin with ezetimibe (Vytorin) should treat this list with real care, since eight of its 184 entries are rated major and some involve everyday foods. Most of the list, 121 ingredients, runs through the CYP3A4 enzyme that clears simvastatin, and the traffic goes both ways.”

Reviewed by 2 · Jul 18, 2026

Open the simvastatin/ezetimibe 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 simvastatin/ezetimibe 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 simvastatin/ezetimibe 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 simvastatin/ezetimibe
Top 25%

#453 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
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
292 Moderate 2,537 No 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

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

Showing the 60 most looked-up of 2,537 medications checked with no known interaction — see the full Flaxseed Oil list.

See the full Flaxseed Oil interactions page
See every supplement checked against simvastatin/ezetimibe, ranked by severity
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
Flaxseed Oil monograph › Uses, safety, and every drug interaction in one place simvastatin/ezetimibe supplement interactions › Every supplement checked against simvastatin/ezetimibe, ranked by severity Supplement interaction checker › Check any supplement or product against your medications Browse medications A–Z › Every drug we've checked against herbs & supplements Ask a pharmacist › Free, personal answer from our licensed team
Pharmacist Counseling Corner

Taking Flaxseed Oil and simvastatin/ezetimibe Together: Common Questions

Can you take Flaxseed Oil with simvastatin/ezetimibe?
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 simvastatin/ezetimibe 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 simvastatin/ezetimibe 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.