Drug & supplement interaction

Flaxseed + Tolbutamide

Tolbutamide brand name: Orinase.

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

Flaxseed has a moderate interaction with Tolbutamide. Theoretically, flaxseed might have additive effects when used with antidiabetes drugs and increase the risk for hypoglycemia.

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

Flaxseed and Tolbutamide

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

Moderate

ANTIDIABETES DRUGS

Why this applies to Tolbutamide

Tolbutamide falls under ANTIDIABETES DRUGS — the group Flaxseed interacts with.

Theoretically, flaxseed might have additive effects when used with antidiabetes drugs and increase the risk for hypoglycemia.
Some clinical research suggests that flaxseed can lower blood glucose levels.
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 thing to keep in mind: Tolbutamide already works by pushing your pancreas to release more insulin, which brings your blood sugar down. Flaxseed, on its own, may nudge blood sugar a little lower too. So when you pair them, those two effects can stack up, and your numbers could dip lower than you expect. That's hypoglycemia, and with tolbutamide it can show up as shakiness, sweating, dizziness, hunger, or feeling confused.

The good news is this concern is mostly theoretical and based on modest research, so it's not a reason to panic. A sprinkle of flaxseed on your oatmeal is unlikely to cause trouble. Bigger, concentrated supplement doses are where I'd pay closer attention. Keep checking your sugars, and chat with your pharmacist or doctor before adding a flaxseed supplement.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Cunnane SC, Ganguli S, Menard C, et al. High alpha-linolenic acid flaxseed (Linum usitatissimum): some nutritional properties in humans. Br J Nutr 1993;69:443-53.
  2. Lemay A, Dodin S, Kadri N, et al. Flaxseed dietary supplement versus hormone replacement therapy in hypercholesterolemic menopausal women. Obstet Gynecol 2002;100:495-504.. DOI
  3. Mani UV, Mani I, Biswas M, Kumar SN. An open-label study on the effect of flax seed powder (Linum usitatissimum) supplementation in the management of diabetes mellitus. J Diet Suppl 2011;8:257-65.
  4. Rhee Y, Brunt A. Flaxseed supplementation improved insulin resistance in obese glucose intolerant people: a randomized crossover design. Nutr J 2011;10:44. PubMed
  5. Villarreal-Renteria AI, Herrera-Echauri DD, Rodríguez-Rocha NP, et al. Effect of flaxseed (Linum usitatissimum) supplementation on glycemic control and insulin resistance in prediabetes and type 2 diabetes: A systematic review and meta-analysis of randomi

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 Also Interacts With Other Medications

Flaxseed has 596 moderate known drug interactions in our database — the Tolbutamide one above is one of them. If you take anything else, check it against the full list below.

Moderate 596 No known interaction 2,234 (incl. Tolbutamide)
Taking anything else?

Check Another of Your Medications Against Flaxseed

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

From our Q&A

Questions About Flaxseed or Tolbutamide

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 or Tolbutamide, 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 Tolbutamide

This page covers Flaxseed only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Tolbutamide page lists 305 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Siberian Cocklebur (major), Acai (moderate), Adrafinil (moderate) and African Wild Potato (moderate).

By severity: 2 major · 255 moderate · 48 minor.

From our pharmacist’s overview on the Tolbutamide page

“People take tolbutamide (Orinase) to lower blood sugar in type 2 diabetes, and diabetes is exactly the condition supplement shelves target, which is why this list runs to 305 ingredients and deserves real caution. Of those, 239 also push glucose around, most often downward, so combining them can drive sugar lower than intended.”

Reviewed by 2 · Jul 18, 2026

Open the Tolbutamide interaction page

One more smart check

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

We hold 236 real supplement products containing Flaxseed, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Flaxseed. Your product may carry other ingredients that interact with Tolbutamide too, on top of Flaxseed — 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 and Tolbutamide 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
Top half

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

29 days ago today
Medication Tolbutamide
Steady interest

#2,163 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

What is Flaxseed?

Flaxseed
  • Constipation and digestive health
  • High cholesterol
  • Heart health
  • Menopausal symptoms
  • Blood sugar support

Flaxseed is a nutritious food rich in fiber, omega-3 fats (ALA), and plant compounds called lignans. It is most reliably helpful for constipation and may modestly lower cholesterol, but evidence for many other uses is mixed or limited. It is generally safe as a food, but talk to your pharmacist or doctor before using it as a supplement, especially if you are pregnant or breastfeeding.

Read the full Flaxseed monograph & all interactions
Medication

About Tolbutamide

What Is Tolbutamide Used For?

Brand name: Orinase

  • Tolbutamide is used along with diet and exercise, and sometimes with other medications, to treat type 2 diabetes (condition in which the body does not use insulin normally and, therefore, cannot control the amount of sugar in the blood). Tolbutamide is in a class of medications called sulfonylureas. Tolbutamide lowers blood sugar by causing the pancreas to produce insulin (a natural substance that is needed to break down sugar in the body) and helping the body use insulin efficiently. This medication will only help lower blood sugar in people whose bodies produce insulin naturally. Tolbutamide is not used to treat type 1 diabetes (condition in which the body does not produce insulin and, therefore, cannot control the amount of sugar in the blood) or diabetic ketoacidosis (a serious condition that may occur if high blood sugar is not treated).

  • Over time, people who have diabetes and high blood sugar can develop serious or life-threatening complications, including heart disease, stroke, kidney problems, nerve damage, and eye problems. Taking medication(s), making lifestyle changes (e.g., diet, exercise, quitting smoking), and regularly checking your blood sugar may help to manage your diabetes and improve your health. This therapy may also decrease your chances of having a heart attack, stroke, or other diabetes-related complications such as kidney failure, nerve damage (numb, cold legs or feet; decreased sexual ability in men and women), eye problems, including changes or loss of vision, or gum disease. Your doctor and other healthcare providers will talk to you about the best way to manage your diabetes.

See full Tolbutamide drug information
Keep checking

Other Drugs & Flaxseed

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

0Major
596Moderate
0Minor
2,233No known interaction
596 Moderate 2,233 No interaction
Moderate

596 interactions

Showing 60 of 596 moderate interactions — see all 596 on the Flaxseed page.

No interaction 2,233 drugs checked — show the list

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

Showing the 60 most looked-up of 2,233 medications checked with no known interaction — see the full Flaxseed list.

See the full Flaxseed interactions page
See every supplement checked against Tolbutamide, 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 monograph › Uses, safety, and every drug interaction in one place Tolbutamide supplement interactions › Every supplement checked against Tolbutamide, ranked by severity Tolbutamide drug information › The full plain-English guide to this medication 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 and Tolbutamide Together: Common Questions

Can you take Flaxseed with Tolbutamide?
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 and Tolbutamide 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 Tolbutamide and Flaxseed?

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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.