Drug & supplement interaction

Blueberry + Tolbutamide

Tolbutamide brand name: Orinase.

Minor Interaction
The bottom line Minor

Blueberry has a minor interaction with Tolbutamide. Theoretically, blueberries or blueberry leaf extracts might increase the risk of hypoglycemia when taken with antidiabetes drugs.

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

Blueberry and Tolbutamide

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

Minor

ANTIDIABETES DRUGS

Why this applies to Tolbutamide

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

Theoretically, blueberries or blueberry leaf extracts might increase the risk of hypoglycemia when taken with antidiabetes drugs.
Animal and in vitro research suggests that blueberry and/or blueberry leaf extracts can lower blood glucose levels.
Severity Minor Likelihood Unlikely Evidence D

Interaction has been demonstrated in animal or in lab research but has been shown not to occur in humans..

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

Here's the simple version: tolbutamide (Orinase) already lowers your blood sugar by nudging your pancreas to release more insulin. The thought is that concentrated blueberry or blueberry leaf extracts might push your blood sugar down a little too, so stacking them could in theory add up and leave you running low.

I want to be honest about how thin this evidence is. The concern comes only from lab and animal studies, not from people, and it's rated as a minor, unlikely interaction. Eating blueberries as food is not a worry here. The question is really about high-dose extracts. If you do start one, just be a little more mindful of low-sugar signs like shakiness, sweating, or feeling lightheaded, and check in with your pharmacist or doctor first.

References
  1. Cignarella A, Nastasi M, Cavalli E, Puglisi L. Novel lipid-lowering properties of Vaccinium myrtillus L. leaves, a traditional antidiabetic treatment, in several models of rat dyslipidaemia: a comparison with ciprofibrate. Thromb Res 1996;84:311-22. PubMed
  2. Martineau, L. C., Couture, A., Spoor, D., Benhaddou-Andaloussi, A., Harris, C., Meddah, B., Leduc, C., Burt, A., Vuong, T., Mai, Le P., Prentki, M., Bennett, S. A., Arnason, J. T., and Haddad, P. S. Anti-diabetic properties of the Canadian lowbush bluebe
  3. Vuong, T., Martineau, L. C., Ramassamy, C., Matar, C., and Haddad, P. S. Fermented Canadian lowbush blueberry juice stimulates glucose uptake and AMP-activated protein kinase in insulin-sensitive cultured muscle cells and adipocytes. Can J Physiol Pharma

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

Blueberry Also Interacts With Other Medications

Blueberry has 87 minor 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.

Taking anything else?

Check Another of Your Medications Against Blueberry

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

Everything else you take

See Every Supplement That Interacts With Tolbutamide

This page covers Blueberry 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 Blueberry as Part of a Dietary Supplement Product? Check It for Interactions

We hold 5,076 real supplement products containing Blueberry, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Blueberry. Your product may carry other ingredients that interact with Tolbutamide too, on top of Blueberry — 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 Blueberry 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 Blueberry
Top 5%

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

29 days ago today
Medication Tolbutamide
Steady interest

#1,655 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 Blueberry

What is Blueberry?

  • Antioxidant support
  • Heart health
  • Brain and memory health
  • Blood sugar support
  • Eye health
  • Urinary health

Blueberries are a nutritious fruit rich in antioxidants called anthocyanins, and eating them as part of a balanced diet is healthy and safe for most people. Concentrated supplements are marketed for heart, brain, and blood sugar health, but the evidence is mostly early and not strong enough to promise specific benefits. Enjoy blueberries as food, and talk to your pharmacist before using high-dose extracts.

Read the full Blueberry 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 & Blueberry

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

0Major
0Moderate
87Minor
2,742No known interaction
Minor

87 interactions

Showing 60 of 87 minor interactions — see all 87 on the Blueberry page.

No interaction 2,742 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 Blueberry and Tolbutamide Together: Common Questions

Can you take Blueberry with Tolbutamide?
There is only a minor interaction, which is usually not serious. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Blueberry and Tolbutamide interaction?
We rate it Minor. This interaction is generally not clinically significant, but it remains worth noting and discussing with your pharmacist.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

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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.