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Dietary supplement

Bilberry-20 340 mg Alcohol-Free Ingredients & Drug Interactions

by Nature's Answer

Bilberry-20 340 mg Alcohol-Free label
See full label image
Liquid 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-20 340 mg Alcohol-Free 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-20 340 mg Alcohol-Free is a dietary supplement by Nature's Answer with 1 active ingredient. 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 (Vaccinium myrtillus) fruit extract. 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-20 340 mg Alcohol-Free by Nature's Answer

Ask about any prescription or over-the-counter medication and we check it for interactions with Bilberry-20 340 mg Alcohol-Free by Nature's Answer — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Bilberry-20 340 mg Alcohol-Free by Nature's Answer

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 1 of its 1 active ingredient.
  • No proprietary blends here — you can verify the dose of every single component.

This product contains one active ingredient: bilberry (Vaccinium myrtillus) fruit extract, at 340 mg per serving. Bilberry is a dark purple berry rich in anthocyanidins, compounds traditionally used to support vision and circulation.

The liquid also contains glycerin and purified water as inactive ingredients.

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 support.
  • 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 is mixed and often limited. For night vision, it's rated possibly ineffective — the main use people reach for it.

For age-related cognitive decline, macular degeneration, atherosclerosis, high cholesterol, and chronic venous insufficiency, the research we hold is insufficient to rate whether it works. If you're considering this for a specific condition, talk it over with your doctor to weigh what evidence exists against other options.

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 eaten as food is generally well tolerated, but concentrated supplement safety data is thin and long-term safety isn't well established — so caution is advised. The most common side effects are dark-colored stools (which can be alarming but harmless), flatulence, and mild gastrointestinal discomfort.

A small number of trial participants reported mild-to-moderate gas, and some saw temporary GI upset. Your tongue, teeth, and stools may darken noticeably from bilberry — this is not dangerous, just a visual effect of the pigment.

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 taking this product, double-check with your doctor or pharmacist if you're on blood thinners or antiplatelet drugs (warfarin, aspirin, clopidogrel) — bilberry may increase bleeding risk. Also flag it if you take diabetes medications or erlotinib, or if your liver processes your other drugs through the CYP2E1 enzyme.

The interactions are moderate, but worth confirming.

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 extract may appeal to you if you're interested in eye health or circulation, though the evidence for night vision is weak. If you take blood thinners, diabetes medications, or erlotinib, check with your doctor or pharmacist before adding this — the interaction risk is real.

Even without those medications, discuss with your healthcare provider whether bilberry makes sense for what you're after.

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

Assessment coverage: 1 of 1 active ingredient matched to our full ingredient reviews (monographs). Based on the product label dated Feb 25, 2019.

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-20 340 mg Alcohol-Free, straight from the product label.

Brand Nature's Answer
Barcode (UPC) 083000007538
Net contents 1 fl. Oz.; 30 mL
Market status On market
Date entered into DSLD Feb 25, 2019
DSLD ID 193187
Product type Botanical
Supplement form Liquid
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Kosher
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-20 340 mg Alcohol-Free by Nature's Answer, 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 mL
Maximum serving Sizes:
1 mL
Servings per container
30
UPC/BARCODE
083000007538
IngredientAmount% DV
Bilberry (Vaccinium myrtillus) fruit extract340 mg--

Other ingredients: Glycerin, purified 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.
FDA Disclaimer Statement

These statements have not been evaluated by the FDA. This product is not intended to diagnose, treat, cure, or prevent any disease.

Formula

K Parve

Anthocyanins: The active ingredients naturally present in authenticated Bilberry.

Seals/Symbols

K Parve

Bio-Chelated Cold Extraction Process

General

9421 Rev. 716 AF10

General Statements

Since 1972

Supplying 20 Active Constituents Super concentrated

Brand IP Statement(s)

Advanced Botanical Fingerprint

Discover Nature's Answer

2016 Nature's Answer

Formulation

Alcohol-Free

FDA Statement of Identity

Herbal Supplement

Suggested/Recommended/Usage/Directions

Suggested Use: As a dietary supplement, take 1 mL (approx. 28 drops) once a day in a small amount of water. Shake well before use.

Precautions

Warning: Keep out of reach of children.

Do not use if safety seal is damaged or missing.

If you are pregnant, nursing, taking any medications, planning any medical procedure or have a medical condition, consult with your healthcare practitioner before use.

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

See for yourself

Bilberry-20 340 mg Alcohol-Free by Nature's Answer label

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

Bilberry-20 340 mg Alcohol-Free 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-20 340 mg Alcohol-Free by Nature's Answer

This is the 1 active ingredient this product is made of. Select it to open its full monograph.

Serving size1 mL Dosage formLiquid Servings per container30 Amounts shown are per serving.

Bilberry (Vaccinium myrtillus) fruit extract

Interacts with
275 drugs
340 mg per serving Form: Anthocyanins

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 (Vaccinium myrtillus) fruit extract monograph & interactions

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

Interaction report

Bilberry-20 340 mg Alcohol-Free by Nature's Answer Drug Interactions

Want to check YOUR meds against Bilberry-20 340 mg Alcohol-Free?

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 (Vaccinium myrtillus) fruit extract 275

Individual Drug Interactions

The ingredients in Bilberry-20 340 mg Alcohol-Free interact with 275 drugs. Click any drug to see the details.

1 of the 1 ingredient in Bilberry-20 340 mg Alcohol-Free interact with drugs. Each result below shows which ingredient is responsible. Bilberry (Vaccinium myrtillus) fruit extract

Each ingredient & the kinds of drugs it affects

For each ingredient in Bilberry-20 340 mg Alcohol-Free 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.

Bilberry (Vaccinium myrtillus) fruit extract4 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 (Vaccinium myrtillus) fruit extract full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Bilberry-20 340 mg Alcohol-Free, from the product label.

Nature's Answer

See all Nature's Answer products
Name
Nature's Answer
City
Hauppauge
State
NY
ZipCode
11788-3943
Phone Number
(800) 439-2324
Web Address
www.naturesanswer.com
Pharmacist Counseling Corner

Bilberry-20 340 mg Alcohol-Free by Nature's Answer: Common Questions

Does Bilberry-20 340 mg Alcohol-Free by Nature's Answer interact with any medications?
Yes. Based on its ingredients, Bilberry-20 340 mg Alcohol-Free 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-20 340 mg Alcohol-Free contains a single active ingredient, and that one ingredient can interact with many different medications on its own. We check it against each medication and show the mechanism 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 during pregnancy or breastfeeding?
Yes, bilberry is rated likely safe in pregnancy and lactation. That said, concentrated supplements haven't been studied much in pregnant or nursing people, so it's smart to run it by your doctor or midwife first.
Will my stools really turn dark?
Yes — bilberry's dark purple pigment can stain your stool, tongue, and even teeth a dark blue, green, or black. It's harmless, just a visual effect. In one study, about half the people taking bilberry extract saw this happen.
Does bilberry actually improve night vision?
The evidence says it's possibly ineffective for night vision — the most common reason people buy it. The research doesn't back that use well, so manage your expectations.
What's in this besides the bilberry extract?
Just glycerin and purified water as inactive ingredients — no fillers or binders beyond those.
Can bilberry cause gas or stomach upset?
Yes. Gastrointestinal discomfort, flatulence, and dark stools are the most common side effects. A small number of people in trials reported mild-to-moderate gas, and some had temporary stomach upset — so start slowly and see how your belly responds.

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

Not sure if Bilberry-20 340 mg Alcohol-Free 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-20 340 mg Alcohol-Free label
Go deeper

The Full Monographs Behind Bilberry-20 340 mg Alcohol-Free’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-20 340 mg Alcohol-Free'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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