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Dietary supplement

Extra Strength Biberry Leaf 450 mg 4:1 Extract Ingredients & Drug Interactions

by TerraVita Premium Collection

Extra Strength Biberry Leaf 450 mg 4:1 Extract 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 Extra Strength Biberry Leaf 450 mg 4:1 Extract 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

Extra Strength Biberry Leaf 450 mg 4:1 Extract is a dietary supplement by TerraVita Premium Collection 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 leaf extract. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Extra Strength Biberry Leaf 450 mg 4:1 Extract by TerraVita Premium Collection

Ask about any prescription or over-the-counter medication and we check it for interactions with Extra Strength Biberry Leaf 450 mg 4:1 Extract by TerraVita Premium Collection — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Extra Strength Biberry Leaf 450 mg 4:1 Extract by TerraVita Premium Collection

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 11, 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 has one active ingredient: bilberry leaf extract, a concentrated form (4:1 extract) that delivers 450 mg per capsule. The extract is enclosed in a gelatin capsule with water as the only other ingredient.

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 limited. Night vision appears possibly ineffective based on the data we hold.

For age-related cognitive decline, age-related macular degeneration (AMD), atherosclerosis, high cholesterol, and chronic venous insufficiency, the evidence isn't strong enough to rate whether it works. If you're considering this product for any of these reasons, talk with your pharmacist about what the research actually supports.

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 supplement safety and long-term effects are not well studied. The main side effects reported with bilberry extracts and juice are dark-colored stools (which can look bluish or black), flatulence, and mild stomach discomfort — these were temporary in most cases.

One small trial reported mild-to-moderate gas in about one-third of patients, though that study had limitations. A small number of people have also noticed slight discoloration of the tongue or teeth.

Because safety data for concentrated supplements is limited, caution is advised with long-term or high-dose use.

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 starting this product, double-check any blood thinners or antiplatelet drugs you take — bilberry may increase bleeding risk (Moderate). Also flag diabetes medications that lower blood sugar, cancer drugs like erlotinib, and any medication broken down by CYP2E1, where the extract might reduce effectiveness (all Moderate).

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.

If you take blood thinners, diabetes medications, or cancer drugs like erlotinib, check your specific medications with the tool below before using this product. Bilberry leaf is generally well tolerated but may cause dark stools or mild stomach upset.

The evidence for its effectiveness is thin, so know what you're taking it for.

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 21, 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 Extra Strength Biberry Leaf 450 mg 4:1 Extract, straight from the product label.

Brand TerraVita Premium Collection
Barcode (UPC) 064435112455
Net contents 100 Capsule(s)
Market status On market
Date entered into DSLD Feb 21, 2023
DSLD ID 286465
Product type Botanical
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years)
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 Extra Strength Biberry Leaf 450 mg 4:1 Extract by TerraVita Premium Collection, 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
100
UPC/BARCODE
064435112455
IngredientAmount% DV
Bilberry leaf extract450 mg--

Other ingredients: Gelatin, 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 Statement of Identity

A Dietary Supplement

Brand IP Statement(s)

Copyright 2004 TerraVita - Distributed by ZooScape LLC, All Rights Reserved.

Suggested/Recommended/Usage/Directions

Directions Take 1 capsule, 3 times daily, with meals.

General Statements

TerraVita is an exclusive line of premium natural products that use the finest, purest and most potent ingredients in the world. TerraVita's hallmarks are the highest possible standards of purity, potency, stability and freshness. All products are prepared with the greatest quality control, from raw materials through the entire manufacturing process, right up to the moment your product is sealed for freshness and shipped to you.

Please recycle!

FDA Disclaimer Statement

Statements not evaluated by FDA. Product not intended to diagnose, treat, cure, or prevent any disease.

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

See for yourself

Extra Strength Biberry Leaf 450 mg 4:1 Extract by TerraVita Premium Collection label

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

Extra Strength Biberry Leaf 450 mg 4:1 Extract 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 Extra Strength Biberry Leaf 450 mg 4:1 Extract by TerraVita Premium Collection

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

Serving size1 Capsule(s) Dosage formCapsule Servings per container100 Amounts shown are per serving.

Bilberry leaf extract

Interacts with
275 drugs
450 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 leaf extract monograph & interactions

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

Interaction report

Extra Strength Biberry Leaf 450 mg 4:1 Extract by TerraVita Premium Collection Drug Interactions

Want to check YOUR meds against Extra Strength Biberry Leaf 450 mg 4:1 Extract?

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 leaf extract 275

Individual Drug Interactions

The ingredients in Extra Strength Biberry Leaf 450 mg 4:1 Extract interact with 275 drugs. Click any drug to see the details.

1 of the 1 ingredient in Extra Strength Biberry Leaf 450 mg 4:1 Extract interact with drugs. Each result below shows which ingredient is responsible. Bilberry leaf extract

Each ingredient & the kinds of drugs it affects

For each ingredient in Extra Strength Biberry Leaf 450 mg 4:1 Extract 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 leaf 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 leaf extract full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Extra Strength Biberry Leaf 450 mg 4:1 Extract, from the product label.

TerraVita Premium Collection

See all TerraVita Premium Collection products
Name
TerraVita Fine Whole Herbs
City
Brampton
State
Ontario
Pharmacist Counseling Corner

Extra Strength Biberry Leaf 450 mg 4:1 Extract by TerraVita Premium Collection: Common Questions

Does Extra Strength Biberry Leaf 450 mg 4:1 Extract by TerraVita Premium Collection interact with any medications?
Yes. Based on its ingredients, Extra Strength Biberry Leaf 450 mg 4:1 Extract 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?
Extra Strength Biberry Leaf 450 mg 4:1 Extract 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 leaf safe during pregnancy or while breastfeeding?
The safety data rates bilberry as likely safe in pregnancy and lactation. That said, supplement safety is always an individual decision — talk with your OB or pharmacist before starting, especially if you're taking other medications.
Will my stools really turn black?
Yes — dark-colored, bluish, or even black stools are a known side effect of bilberry products. This is harmless discoloration from the pigments in bilberry and should go away when you stop taking it. A small number of people have also noticed slight discoloration of the tongue or teeth.
Will this help my night vision?
The evidence suggests it probably won't. Night vision is rated possibly ineffective in the research we hold, so bilberry isn't a reliable choice if that's your main goal.
What's a 4:1 extract?
It means the extract is concentrated — roughly 4 pounds of raw bilberry leaf material were processed down into 1 pound of extract, so each capsule packs more active compounds than the whole leaf would.
Can I take this long-term?
Long-term safety data for bilberry supplements is limited, so caution is advised with extended use. Stick to food amounts if you can, and talk with your pharmacist about whether extended supplementation makes sense for you.

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

Not sure if Extra Strength Biberry Leaf 450 mg 4:1 Extract 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.

Extra Strength Biberry Leaf 450 mg 4:1 Extract label
Go deeper

The Full Monographs Behind Extra Strength Biberry Leaf 450 mg 4:1 Extract’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

Extra Strength Biberry Leaf 450 mg 4:1 Extract'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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