Interactions on record — worth a quick check against your medications. Based on 1 of 2 ingredients. Check your meds →
Dietary supplement

Bilberry Ingredients & Drug Interactions

by Kroeger Herb Products Co.

Bilberry label
See full label image
Capsule Category: Botanical
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Bilberry against your medications. The heart of this page is the interaction checker and the full interaction report — how this product’s ingredients may interact with prescription and over-the-counter medicines you may be taking.

Around that, we add a pharmacist’s high-level view of the product as a whole — what’s inside, the evidence for its stated use, how transparent the label is, and what safety data exists — so you can see the full picture in one place. It’s educational information from our licensed clinical databases and the clinical staff at HelloPharmacist — not medical advice — and we don’t sell or endorse products. Our editorial policy

The interaction bottom line Most serious interaction: Moderate

Bilberry is a dietary supplement by Kroeger Herb Products Co. with 2 active ingredients. Its ingredients are commonly taken for eye and vision health, antioxidant support, diarrhea and digestive upset.Based on those ingredients, 275 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Bilberry. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Bilberry by Kroeger Herb Products Co.

Ask about any prescription or over-the-counter medication and we check it for interactions with Bilberry by Kroeger Herb Products Co. — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Bilberry by Kroeger Herb Products Co.

Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Jul 16, 2026

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 2 of its 2 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

This product contains two active ingredients: bilberry and bilberry fruit extract, dried. Both come from the same plant and work together to deliver the fruit's active compounds.

The capsules themselves are vegetarian-sourced, with water as the other ingredient listed.

Does it work?

Leans against
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed
Leans against

The strongest graded evidence we hold for the stated purpose leans against a benefit.

Why this rating?
  • The label markets this product for: Eye and vision health.
  • We looked for evidence on: Age-related macular degeneration (AMD), Asthenopia (eye strain), Cataracts, Diabetic retinopathy, Dry eye, Glaucoma — and 4 related terms.
  • The closest evidence on file: Bilberry is rated "Possibly Ineffective" for Night vision (Natural Medicines).
  • Also on file: Bilberry is rated "Insufficient Reliable Evidence To Rate" for Age-related macular degeneration (AMD), Cataracts, Diabetic retinopathy, Dry eye, and more.

The evidence for bilberry's effectiveness is limited in the data we hold. Night vision — a common reason people take bilberry — is rated possibly ineffective.

For age-related cognitive decline, age-related macular degeneration (AMD), atherosclerosis, high cholesterol (hyperlipidemia), and chronic venous insufficiency (CVI), there is insufficient reliable evidence to rate how well it works. If you're considering bilberry for a specific reason, talk with your doctor about whether the current science supports that use.

The evidence, ingredient by ingredient Bilberry

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 1 of the 1 matched ingredient.
  • Pregnancy & breastfeeding safety ratings cover 1 of 1.
  • General safety write-ups exist for 1 of 1.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Bilberry fruit is generally well tolerated when taken as a food. However, the safety data for concentrated supplements is limited, and long-term safety evidence is lacking — it's best to avoid supplement doses without talking to your healthcare provider first.

The most common side effects are dark-colored stools (reported in up to 50% of people in one study), flatulence, and gastrointestinal discomfort. Your tongue, teeth, and feces may temporarily discolor dark blue to black.

These effects are usually mild, but if you have a sensitive stomach or digestive conditions, mention bilberry to your doctor or pharmacist first. Bilberry is rated likely safe in pregnancy and breastfeeding, though overall supplement data during these periods remain limited.

Side effects, ingredient by ingredient Bilberry

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

The most serious documented interaction for these ingredients is Moderate. Check your medications for a personalized result.

Why this rating?
  • 1 of the 1 matched ingredient can interact with medications — Bilberry.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; diabetes medications.
  • For scale: 275 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before you take this bilberry product, double-check with your doctor or pharmacist if you're on blood thinners or antiplatelet drugs (like warfarin or aspirin) — bilberry may increase bleeding risk. Also check if you take diabetes medications, drugs metabolized by the liver enzyme CYP2E1, or erlotinib (Tarceva).

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with graded evidence leaning against its stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

Bilberry may be worth considering if you're looking for antioxidant support, but the evidence it actually works for common uses like night vision is weak. If you take blood thinners, diabetes drugs, or erlotinib, you need to check with your doctor or pharmacist before starting — the interactions are real enough to matter.

Expect dark stools and possible stomach upset. Talk it over with your own healthcare provider to decide if it's right for you.

Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI

Assessment coverage: 2 of 2 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Jan 23, 2023.

This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed

At a glance

General information

Key facts about Bilberry, straight from the product label.

Brand Kroeger Herb Products Co.
Barcode (UPC) 696916115008
Net contents 90 Vegetarian Capsule(s)
Market status On market
Date entered into DSLD Jan 23, 2023
DSLD ID 282497
Product type Botanical
Supplement form Capsule
Dietary claims / uses All Other
Intended target group(s) Adult (18 - 50 Years), Women (not pregnant or lactating), Gluten Free
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for Bilberry by Kroeger Herb Products Co., sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
1 Capsule(s)
Maximum serving Sizes:
1 Capsule(s)
Servings per container
90
UPC/BARCODE
696916115008
IngredientAmount% DV
Bilberry300 mg--
Bilberry Fruit Extract, Dried50 mg--

Other ingredients: Vegetarian Source Capsules, Water

Tap any ingredient to jump to its full detail below.

Label statements
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
Suggested/Recommended/Usage/Directions

Directions: 1 capsule 3 times daily.

Precautions

Do not purchase if seal is broken.

Keep out of reach of children.

Do not use during pregnancy unless recommended by your health care professional.

Formulation

Contains no: yeast, wheat, gluten, corn, rice, soy or preservatives.

Complete Concentrates

Only Complete Concentrates use standardized, full-profile herbal extracts of an all-natural water or water/alcohol extraction process without harmful solvents, such as acetone, hexane or denatured alcohol, and without excipients, such as maltodextrin. Complete Concentrates are made with an active base of pure herb without any fillers, binders or flowing agents.

Formula

Bilberry Standardized to 25% anthocyanosides using a full-profile, natural extraction in a base of raw Bilberry leaf.

General Statements

Optima Valitudine "Excellent Health"

FDA Statement of Identity

Herbal Supplement

Is this label outdated? Report a formula or label change and our pharmacy team will review it.

See for yourself

Bilberry by Kroeger Herb Products Co. label

The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.

Bilberry label

Label images are published by the NIH Dietary Supplement Label Database for the version of this product on file. Always read your actual product label.

View the full label (PDF)
What’s inside

The Ingredients in Bilberry by Kroeger Herb Products Co.

These are the 2 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 Capsule(s) Dosage formCapsule Servings per container90 Amounts shown are per serving.

Most supplement products combine several ingredients, and a medication can interact with the product through any one of them. Each ingredient below shows whether it has known drug interactions.

Bilberry

Interacts with
275 drugs
300 mg per serving

Bilberry is a blueberry-like fruit rich in antioxidant plant compounds called anthocyanins, and it has a long history of traditional use for eye healt...

Bilberry monograph & interactions

Bilberry Fruit Extract, Dried

Interacts with
275 drugs
50 mg per serving Form: Anthocyanosides

Bilberry is a blueberry-like fruit rich in antioxidant plant compounds called anthocyanins, and it has a long history of traditional use for eye healt...

Bilberry Fruit Extract, Dried monograph & interactions

Other (inactive) ingredients: Vegetarian Source Capsules, Water. These complete the product’s ingredient list but are not active constituents.

Interaction report

Bilberry by Kroeger Herb Products Co. Drug Interactions

Want to check YOUR meds against Bilberry?

Ask about interactions with your drugs in plain English — “Can I take it with lisinopril?” — and we find you the answer in seconds, ingredient by ingredient.

 Go to the checker
275Drugs
275 Moderate

Ingredients driving the most interactions

Bilberry 275

Individual Drug Interactions

The ingredients in Bilberry interact with 275 drugs. Click any drug to see the details.

1 of the 2 ingredients in Bilberry interact with drugs. Each result below shows which ingredient is responsible. Bilberry

Each ingredient & the kinds of drugs it affects

For each ingredient in Bilberry with known interactions, here are the types of medications it can affect. Open any type for the detail — or search your exact drug in the checker above.

Bilberry4 drug types · 275 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, bilberry fruit extract might increase the risk of bleeding when taken with anticoagulant or antiplatelet drugs.
In vitro, animal, and clinical research suggest that anthocyanidin extracts from bilberry can inhibit platelet aggregation.

Likelihood Possible Evidence D
Antidiabetes Drugs

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.

Likelihood Possible Evidence D
Cytochrome P450 2E1 (Cyp2E1) Substrates

Theoretically, bilberry fruit extract might decrease levels of drugs metabolized by CYP2E1.
Animal research shows that exposure to small concentrations of bilberry extract in drinking water for around one month increased CYP2E1 activity by 31%. However, exposure over a 2-month period did not increase CYP2E1 activity. This effect has not been reported in humans.

Likelihood Possible Evidence D
Erlotinib (Tarceva)

Theoretically, bilberry fruit extract might reduce the efficacy of erlotinib.
In vitro research suggests that bilberry fruit extract and its constituents, delphinidin and delphinidin-3-O-glucoside, inhibit the activity of erlotinib. This interaction has not been reported in humans.

Likelihood Possible Evidence D
Bilberry full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Bilberry, from the product label.

Kroeger Herb Products Co.

See all Kroeger Herb Products Co. products
Name
Kroeger Herb Products Co., Inc.
Street Address
1500 Kansas Avenue, Unit 4F
City
Longmont
State
CO
ZipCode
80501
Phone Number
303-443-0261
Pharmacist Counseling Corner

Bilberry by Kroeger Herb Products Co.: Common Questions

Does Bilberry by Kroeger Herb Products Co. interact with any medications?
Yes. Based on its ingredients, Bilberry has a known interaction with 275 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Bilberry contains 2 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Is bilberry safe if I'm pregnant or breastfeeding?
Bilberry is rated likely safe in pregnancy and lactation. That said, supplement safety data during these periods is still limited overall. If you're pregnant or breastfeeding, talk with your doctor or pharmacist before starting any supplement, including this one.
Will bilberry really improve my night vision?
Not based on the evidence we hold. Night vision is rated possibly ineffective for bilberry. If better vision is your goal, this may not be the right supplement.
What are the most common side effects?
Dark-colored stools are the most frequent — up to 50% of people reported dark green stools in one study. You may also experience flatulence and gastrointestinal discomfort. Your tongue may temporarily turn dark blue or black as well. These effects are usually mild and temporary.
Why does bilberry make my stools dark?
Bilberry's deep color comes from anthocyanins, plant pigments that your body doesn't fully break down. They pass through and color your stool, tongue, and sometimes even your teeth. This is harmless and temporary.
Can I take bilberry if I have diabetes and take medication for it?
You'll need to check with your doctor or pharmacist first. Bilberry itself may lower blood sugar, so taking it alongside diabetes drugs could raise your risk of low blood sugar (hypoglycemia). This is a Moderate-severity interaction.
How much bilberry does this product contain?
The exact amounts of bilberry and bilberry fruit extract per capsule are not provided in the product information. Check the label on the bottle or contact the manufacturer for that detail.

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

Not sure if Bilberry is safe with your meds?

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Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

Bilberry label
Go deeper

The Full Monographs Behind Bilberry’s Ingredients

Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.

Herb & supplement monograph

Bilberry

Interacts with 275 drugs

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...

Read the full Bilberry monograph →
Sources

Sources & How We Checked

Bilberry's label data comes from the NIH Dietary Supplement Label Database; the ingredient interaction data is from the Natural Medicines database, reviewed by our pharmacists.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

The 14 references behind this product’s interaction data

Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.

Bilberry 14 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. Morazzoni P, Magistretti MJ. Activity of Myrtocyan, an anthosyanoside complex from Vaccinium myrtillus (VMA), on platelet aggregation and adhesiveness. Fitoterapia 1990;61:13-21.
  3. Erlund, I., Koli, R., Alfthan, G., Marniemi, J., Puukka, P., Mustonen, P., Mattila, P., and Jula, A. Favorable effects of berry consumption on platelet function, blood pressure, and HDL cholesterol. Am J Clin Nutr 2008;87(2):323-331. PubMed
  4. Hawrelak, J. A. and Myers, S. P. Effects of two natural medicine formulations on irritable bowel syndrome symptoms: a pilot study. J Altern Complement Med 2010;16(10):1065-1071. PubMed
  5. Morazzoni P and Magistretti MJ. Effects of Vaccinium myrtillus anthocyanosides on prostacyclin-like activity in rat arterial issue. Fitoterapia 1986;57:11-14.
  6. Pulliero G, Montin S, Bettini V, and et al. Ex vivo study of the inhibitory effects of Vaccinium myrtillus anthocyanosides on human platelet aggregation. Fitoterapia 1989;60:69-75.
  7. Bottecchia D. Preliminary report on the inhibitory effect of vaccinium myrtillus anthocyanosides on platelet aggregation and clot retraction. Fitoterapia 1987;48:3-8.
  8. Fdez, M., Zaragoza, F., and Alvarez, P. In vitro platelet aggregation effects of anthocyanosides of vaccinium myrtilus L. Anales de la Real Academia de Farmacia 1983;49:79-90.
  9. Biedermann L, Mwinyi J, Scharl M, Frei P, Zeitz J, Kullak-Ublick GA, et al. Bilberry ingestion improves disease activity in mild to moderate ulcerative colitis-an open pilot study. 2013 May;7(4):271-9. PubMed
  10. 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
  11. Aichinger G, Pahlke G, Nagel LJ, Berger W, Marko D. Bilberry extract, its major phenolic compounds, and soy isoflavone genistein antagonize the cytostatic drug erlotinib in human epithelial cells. Food Funct 2016;7(8):3628-36.
  12. Prokop J, Lněničková K, Cibicek N, et al. Effect of bilberry extract (Vaccinium myrtillus L.) on drug-metabolizing enzymes in rats. Food Chem Toxicol 2019;129:382-90. PubMed
  13. Chan SW, Chu TTW, Choi SW, Benzie IFF, Tomlinson B. Impact of short-term bilberry supplementation on glycemic control, cardiovascular disease risk factors, and antioxidant status in Chinese patients with type 2 diabetes. Phytother Res 2021. Online ahead o PubMed
  14. Bøhn SK, Myhrstad MCW, Thoresen M, et al. Bilberry/red grape juice decreases plasma biomarkers of inflammation and tissue damage in aged men with subjective memory impairment -a randomized clinical trial. BMC Nutr 2021;7(1):75. PubMed

See these in context on the Bilberry monograph →

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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