Drug & supplement interaction

Bilberry + Linagliptin

Linagliptin brand name: Tradjenta.

Moderate Interaction
The bottom line Moderate

Bilberry has a moderate interaction with Linagliptin. Theoretically, bilberry leaf or fruit extract may increase the risk of hypoglycemia when taken with antidiabetes drugs.

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

Bilberry and Linagliptin

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

Moderate

ANTIDIABETES DRUGS

Why this applies to Linagliptin

Linagliptin falls under ANTIDIABETES DRUGS — the group Bilberry interacts with.

Theoretically, bilberry leaf or fruit extract may increase the risk of hypoglycemia when taken with antidiabetes drugs.
Animal research suggests that bilberry leaf extract might have blood glucose-lowering activity. Also, one small clinical trial in patients with type 2 diabetes shows that taking bilberry fruit extract 470 mg as a single dose prior to an oral glucose tolerance test lowers plasma glucose levels when compared with placebo.
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 simple version: bilberry itself may gently nudge your blood sugar downward. Since Tradjenta (linagliptin) is already working to lower your numbers, stacking the two could add up and push your blood sugar a little too low. With low blood sugar you might feel shaky, sweaty, dizzy, irritable, or get a fast heartbeat.

I want to keep this in perspective, though. The evidence here is mostly animal studies plus one small human test, so this is more of a theoretical concern than a proven problem. Eating bilberries as food is very unlikely to matter, but concentrated leaf or fruit extracts are where I'd be a bit more cautious. If you want to try a bilberry supplement, check with your pharmacist or doctor first and keep an eye on your glucose readings.

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. Hoggard N, Cruickshank M, Moar KM, Bestwick C, Holst J, Russell W, et al. A single supplement of a standardized bilberry (Vaccinium myrtillus L.) extract (36% wet weight anthocyanins) modifies glycaemic response in individuals with type 2 diabetes control

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

Bilberry Also Interacts With Other Medications

Bilberry has 274 moderate known drug interactions in our database — the Linagliptin 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 Bilberry

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

Everything else you take

See Every Supplement That Interacts With Linagliptin

This page covers Bilberry only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Linagliptin page lists 284 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Siberian Cocklebur (major), St. John's Wort (major), Acai (moderate) and Adrafinil (moderate).

By severity: 3 major · 240 moderate · 41 minor.

From our pharmacist’s overview on the Linagliptin page

“Linagliptin (Tradjenta) helps people with type 2 diabetes bring blood sugar down, so most of the 284 supplements and herbs on this page interact for one basic reason: they lower glucose too, and stacking them can drop you into hypoglycemia. I'd read this list with genuine care rather than a shrug.”

Reviewed by 2 · Jul 18, 2026

Open the Linagliptin interaction page

One more smart check

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

We hold 3,883 real supplement products containing Bilberry, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Bilberry. Your product may carry other ingredients that interact with Linagliptin too, on top of Bilberry — 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 Bilberry and Linagliptin 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 Bilberry
Top 10%

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

29 days ago today
Medication Linagliptin
Top half

#1,058 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 Bilberry

What is Bilberry?

Bilberry
  • Eye and vision health
  • Antioxidant support
  • Diarrhea and digestive upset
  • Circulation and vein health
  • Blood sugar support

Bilberry is a blueberry-like fruit rich in antioxidant plant compounds called anthocyanins, and it has a long history of traditional use for eye health, circulation, and mild diarrhea. While it is generally well tolerated as a food and supplement, strong scientific proof for most health claims is limited. Talk with your pharmacist or doctor before using bilberry supplements, especially if you are pregnant, breastfeeding, or have a health condition.

Read the full Bilberry monograph & all interactions
Medication

About Linagliptin

What Is Linagliptin Used For?

Brand name: Tradjenta

Tradjenta (linagliptin) is used to help control blood sugar in adults with type 2 diabetes. It is meant to be used together with healthy eating and regular exercise, not as a replacement for them.

Linagliptin is not for type 1 diabetes, and it has not been studied in people with a history of pancreatitis.

See full Linagliptin drug information
Keep checking

Other Drugs & Bilberry

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

0Major
274Moderate
0Minor
2,555No known interaction
Moderate

274 interactions

Showing 60 of 274 moderate interactions — see all 274 on the Bilberry page.

No interaction 2,555 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 Bilberry and Linagliptin Together: Common Questions

Can you take Bilberry with Linagliptin?
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 Bilberry and Linagliptin 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 Linagliptin and Bilberry?

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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.