Major interaction on record — check this product against your medications before combining. Based on 4 of 5 ingredients. Check your meds →
Dietary supplement

Bilberry with Eyebright & Elderberry Ingredients & Drug Interactions

by Windmill Natural Vitamins

Bilberry with Eyebright & Elderberry label
See full label image
Tablet Or Pill Category: Botanical With Nutrients
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Bilberry with Eyebright & Elderberry 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: Major

Bilberry with Eyebright & Elderberry is a dietary supplement by Windmill Natural Vitamins with 5 active ingredients. Its ingredients are commonly taken for bone health and osteoporosis prevention, dietary calcium deficiency, heartburn relief (calcium carbonate antacids).Based on those ingredients, 556 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Bilberry, Powder, Calcium, Elderberry Fruit 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 Bilberry with Eyebright & Elderberry by Windmill Natural Vitamins

Ask about any prescription or over-the-counter medication and we check it for interactions with Bilberry with Eyebright & Elderberry by Windmill Natural Vitamins — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of Bilberry with Eyebright & Elderberry by Windmill Natural Vitamins

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 5 of its 5 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

This supplement contains five active ingredients. Calcium supports bone and kidney health.

Eyebright powder and bilberry powder (listed twice in the formula) are herbal extracts traditionally used for eye health, though evidence for their effectiveness is limited or absent. Elderberry fruit extract is included for its antioxidant properties.

The remaining ingredients are inactive — they're fillers, binders, and capsule materials like microcrystalline cellulose, dicalcium phosphate, and magnesium stearate.

Does it work?

Not established
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
Not established

The graded evidence we hold for these ingredients covers different conditions than the ones this product is marketed for, so there's no established rating for its stated use.

Why this rating?
  • The label markets this product for: Eye health and immune support.
  • We looked for evidence on: Age-related macular degeneration (AMD), Asthenopia (eye strain), Blepharitis, Cataracts, Common cold, Conjunctivitis — and 4 related terms.
  • The closest evidence on file: Eyebright is rated "Insufficient Reliable Evidence To Rate" for Common cold (Natural Medicines).
  • Also on file: Eyebright is rated "Insufficient Reliable Evidence To Rate" for Blepharitis, Asthenopia (eye strain), Conjunctivitis.
  • Also on file: Bilberry is rated "Insufficient Reliable Evidence To Rate" for Age-related macular degeneration (AMD), Cataracts, Diabetic retinopathy.

Calcium has solid evidence for kidney disease and digestive upset, and is likely effective for osteoporosis. The herbal ingredients tell a different story.

For eyebright, the evidence we hold shows insufficient reliable data for hay fever, colds, coughs, sore throats, and sinus problems — conditions it's traditionally used for. Bilberry's evidence is also limited; it's possibly ineffective for night vision and insufficient for age-related eye disease, hardened arteries, and other conditions.

Elderberry similarly lacks reliable evidence for hay fever, heart health, fatigue, lung disease, cognitive function, and respiratory infections.

The evidence, ingredient by ingredient Calcium Eyebright Elderberry 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 4 of the 4 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 4 of 4.
  • General safety write-ups exist for 4 of 4.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Calcium is generally well tolerated at recommended doses, though high amounts can cause problems. Common side effects are belching, constipation, diarrhea, gas, and stomach upset.

There's concern that very high daily doses (over 1,500–2,000 mg) may be linked to prostate cancer risk and possibly cardiovascular risk, though research is mixed. Calcium is likely safe during pregnancy and lactation when you stay within recommended amounts.

Eyebright is likely safe in small amounts as a tea but carries caution about using homemade eye drops due to infection risk; it should be avoided in pregnancy and while breastfeeding. Bilberry fruit is generally well tolerated as food or supplement, though long-term safety data are limited; food amounts are fine, but supplement doses are best avoided in pregnancy and breastfeeding.

It may cause dark stools, gas, and tongue discoloration. Elderberry from ripe fruit is well tolerated; raw or unripe berries and seeds can be toxic and cause nausea, vomiting, and severe diarrhea.

There's one rare case of liver injury linked to elderberry; it should be avoided in pregnancy and while breastfeeding.

Side effects, ingredient by ingredient Calcium Eyebright Elderberry Bilberry

Meds to double-check

Major interaction found
Known Interaction Concern · database check
Major identified

At least one ingredient has a documented Major-severity interaction. Check your medications for a personalized result.

Why this rating?
  • 4 of the 4 matched ingredients can interact with medications — Eyebright, Bilberry, Elderberry, Calcium.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; diabetes medications; heart-rhythm medications; lithium.
  • For scale: 556 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 take HIV integrase inhibitors (dolutegravir, elvitegravir), the antibiotic ceftriaxone, levothyroxine (thyroid medication), sotalol (heart rhythm drug), calcipotriene (psoriasis cream), diltiazem or similar heart drugs, blood thinners (anticoagulants) or antiplatelet drugs, diabetes medications, immunosuppressant drugs, or cancer drugs including pazopanib or erlotinib. Calcium needs careful timing with several of these; others have theoretical interactions that need professional review before you combine them.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with no established evidence rating for its marketed use. Major medication interactions have been identified, and safety information is well characterized.

This product is mostly herbal with a calcium base. Calcium is well studied and effective for bone and kidney health, but the bilberry, eyebright, and elderberry components lack solid evidence for their intended uses.

The main concern is calcium's interaction with certain HIV drugs, thyroid medication, and heart drugs — if you take any of those, check with your doctor or pharmacist before starting. If you're considering this mainly for eye health, talk with your provider about whether the herbal ingredients are the right fit for you, since their effectiveness isn't well established.

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

Assessment coverage: 5 of 5 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Nov 22, 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 with Eyebright & Elderberry, straight from the product label.

Brand Windmill Natural Vitamins
Barcode (UPC) 035046007607
Net contents 60 Tablet(s)
Market status On market
Date entered into DSLD Nov 22, 2023
DSLD ID 299549
Product type Botanical With Nutrients
Supplement form Tablet Or Pill
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Vegan, Vegetarian, Adult (18 - 50 Years), Gluten Free, Dairy Free, Sugar 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 with Eyebright & Elderberry by Windmill Natural Vitamins, 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 Tablet(s)
Maximum serving Sizes:
1 Tablet(s)
Servings per container
60
UPC/BARCODE
035046007607
IngredientAmount% DV
Calcium140 mg11%
Eyebright, Powder350 mg--
Elderberry Fruit Extract15 mg--
Bilberry, Powder5 mg--
Bilberry, Powder5 mg--

Other ingredients: Dicalcium Phosphate, Microcrystalline Cellulose, Stearic Acid, Croscarmellose Sodium, Silica, Magnesium Stearate, Pharmaceutical Glaze

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: Take 1 tablet daily as a dietary supplement or as directed by a healthcare professional.

Precautions

Keep out of reach of children.

Do not purchase if seal is broken.

Warning: Pregnant or lactating women should consult with their physician prior to taking this product.

Storage

Protect from heat, light & moisture. Store in a cool, dry place.

Formulation

Made in the U.S.A. from globally sourced ingredients.

Eye health Immune support

No sugar, wheat, soy, milk, artificial colors, flavors or preservatives Non gmo - gluten free - vegan

Non gmo - gluten free - vegan

FDA Disclaimer Statement

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

Formula

Blueprint standardized herbals

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 with Eyebright & Elderberry by Windmill Natural Vitamins label

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

Bilberry with Eyebright & Elderberry 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 with Eyebright & Elderberry by Windmill Natural Vitamins

These are the 5 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 Tablet(s) Dosage formTablet Or Pill Servings per container60 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.

Calcium

Interacts with
168 drugs
140 mg per serving Form: Dicalcium Phosphate

Calcium is an essential mineral your body needs for strong bones, nerve signaling, and muscle function, and supplements can help fill gaps when diet f...

Calcium monograph & interactions

Eyebright, Powder

Interacts with
86 drugs
350 mg per serving Form: Euphrasia officinalis, Powder

Eyebright is a traditional herb long used for minor eye irritation, redness, and allergy symptoms, but high-quality human studies are very limited. Th...

Eyebright, Powder monograph & interactions

Elderberry Fruit Extract

Interacts with
121 drugs
15 mg per serving Form: Sambucus nigra Fruit Extract

Elderberry is a popular herbal supplement, mainly taken to help with colds and flu. Some small studies suggest it may modestly shorten cold or flu sym...

Elderberry Fruit Extract monograph & interactions

Bilberry, Powder

Interacts with
275 drugs
5 mg per serving Form: Vaccinium myrtillus L., Powder

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, Powder monograph & interactions

Bilberry, Powder

Interacts with
275 drugs
5 mg per serving Form: Vaccinium myrtillus L., Powder

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, Powder monograph & interactions

Other (inactive) ingredients: Dicalcium Phosphate, Microcrystalline Cellulose, Stearic Acid, Croscarmellose Sodium, Silica, Magnesium Stearate, Pharmaceutical Glaze. These complete the product’s ingredient list but are not active constituents.

Interaction report

Bilberry with Eyebright & Elderberry by Windmill Natural Vitamins Drug Interactions

Want to check YOUR meds against Bilberry with Eyebright & Elderberry?

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
556Drugs
7 Major 531 Moderate 18 Minor

Ingredients driving the most interactions

Bilberry, Powder 275
Calcium 168
Elderberry Fruit Extract 121
Eyebright, Powder 86

Individual Drug Interactions

The ingredients in Bilberry with Eyebright & Elderberry interact with 556 drugs. Click any drug to see the details.

4 of the 5 ingredients in Bilberry with Eyebright & Elderberry interact with drugs. Each result below shows which ingredient is responsible. Bilberry, Powder Calcium Elderberry Fruit Extract Eyebright, Powder

Each ingredient & the kinds of drugs it affects

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

Bilberry, Powder4 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, Powder full monograph & interactions

Calcium18 drug types · 168 drugs

Ceftriaxone (Rocephin)

Co-administration of intravenous calcium and ceftriaxone can result in precipitation of a ceftriaxone-calcium salt in the lungs and kidneys.
Avoid administering intravenous calcium in any form, such as parenteral nutrition or Lactated Ringers, within 48 hours of intravenous ceftriaxone. Case reports in neonates show that administering intravenous ceftriaxone and calcium can result in precipitation of a ceftriaxone-calcium salt in the lungs and kidneys. In several cases, neonates have died as a result of this interaction. So far there are no reports in adults; however, there is still concern that this interaction might occur in adults.

Likelihood Probable Evidence D
Dolutegravir (Tivicay)

Calcium seems to reduce levels of dolutegravir.
Advise patients to take dolutegravir either 2 hours before or 6 hours after taking calcium supplements. Pharmacokinetic research suggests that taking calcium carbonate 1200 mg concomitantly with dolutegravir 50 mg reduces plasma levels of dolutegravir by almost 40%. Calcium appears to decrease levels of dolutegravir through chelation.

Likelihood Probable Evidence B
Elvitegravir (Vitekta)

Calcium seems to reduce levels of elvitegravir.
Advise patients to take elvitegravir either 2 hours before or 2 hours after taking calcium supplements. Pharmacokinetic research suggests that taking calcium along with elvitegravir can reduce blood levels of elvitegravir through chelation.

Likelihood Probable Evidence B
Aluminum

Calcium citrate might increase aluminum absorption and toxicity. Other types of calcium do not increase aluminum absorption.
Calcium citrate can increase the absorption of aluminum when taken with aluminum hydroxide. The increase in aluminum levels may become toxic, particularly in individuals with kidney disease. However, the effect of calcium citrate on aluminum absorption is due to the citrate anion rather than calcium cation. Calcium acetate does not appear to increase aluminum absorption.

Likelihood Possible Evidence B
Bictegravir/Emtricitabine/Tenofovir Alafenamide (Biktarvy)

Calcium might decrease levels of bictegravir/emtricitabine/tenofovir alafenamide by reducing its absorption when taken in a fasting state.
Advise patients that bictegravir/emtricitabine/tenofovir alafenamide and calcium can be taken together if taken with food. However, if taken on an empty stomach, bictegravir/emtricitabine/tenofovir alafenamide should not be taken with, or 2 hours after, calcium containing products.

Likelihood Probable Evidence D
Bisphosphonates

Calcium reduces the absorption of bisphosphonates.
Advise patients to take bisphosphonates at least 30 minutes before calcium, but preferably at a different time of day. Calcium supplements decrease absorption of bisphosphonates.

Likelihood Probable Evidence C
Calcipotriene (Dovonex)

Taking calcipotriene with calcium might increase the risk for hypercalcemia.
Calcipotriene is a vitamin D analog used topically for psoriasis. It can be absorbed in sufficient amounts to cause systemic effects, including hypercalcemia. Theoretically, combining calcipotriene with calcium supplements might increase the risk of hypercalcemia.

Likelihood Possible Evidence B
Digoxin (Lanoxin)

Using intravenous calcium with digoxin might increase the risk of fatal cardiac arrhythmias.
Hypercalcemia increases the risk of fatal cardiac arrhythmias with digoxin. However, one retrospective analysis of clinical data suggests that intravenous calcium does not increase the risk of dysrhythmias or mortality in patients receiving digoxin.

Likelihood Possible Evidence B
Diltiazem (Cardizem, Others)

Theoretically, calcium may reduce the therapeutic effects of diltiazem.
Hypercalcemia can reduce the effectiveness of verapamil in atrial fibrillation. Theoretically, calcium might increase this risk of hypercalcemia and reduce the effectiveness of diltiazem.

Likelihood Probable Evidence D
Levothyroxine (Synthroid, Others)

Calcium seems to reduce the absorption and effectiveness of levothyroxine.
Advise patients to take levothyroxine and calcium supplements at least 4 hours apart. Calcium reduces levothyroxine absorption, probably by forming insoluble complexes. Calcium carbonate supplements reduce effectiveness of levothyroxine in patients with hypothyroidism.

Likelihood Probable Evidence B
Lithium

Theoretically, concomitant use of calcium and lithium may increase this risk of hypercalcemia.
Clinical research suggests that long-term use of lithium may cause hypercalcemia in 10% to 60% of patients. Theoretically, concomitant use of lithium and calcium supplements may further increase this risk.

Likelihood Possible Evidence B
Quinolone Antibiotics

Calcium seems to reduce the absorption of quinolone antibiotics.
Advise patients to take oral quinolones at least 2 hours before or 4-6 hours after calcium supplements or calcium-fortified foods. Taking calcium at the same time as oral quinolones can reduce quinolone absorption. Calcium binds to quinolones in the gut.

Likelihood Probable Evidence B
Raltegravir (Isentress)

Calcium may reduce levels of raltegravir.
Pharmacokinetic research shows that taking a single dose of calcium carbonate 3000 mg along with raltegravir 400 mg twice daily modestly decreases the mean area under the curve of raltegravir, but the decrease does not necessitate a dose adjustment of raltegravir. However, a case of elevated HIV-1 RNA levels and documented resistance to raltegravir has been reported for a patient taking calcium carbonate 1 gram three times daily plus vitamin D3 (cholecalciferol) 400 IU three times daily in combination with raltegravir 400 mg twice daily for 11 months. It is thought that calcium reduced raltegravir levels by chelation, leading to treatment failure.

Likelihood Possible Evidence B
Sotalol (Betapace)

Calcium seems to reduce the absorption of sotalol.
Advise patients to separate doses by at least 2 hours before or 4-6 hours after calcium. Calcium appears to reduce the absorption of sotalol, probably by forming insoluble complexes.

Likelihood Possible Evidence B
Tetracycline Antibiotics

Calcium seems to reduce the absorption of tetracycline antibiotics.
Advise patients to take oral tetracyclines at least 2 hours before, or 4-6 hours after calcium supplements. Taking calcium at the same time as oral tetracyclines can reduce tetracycline absorption. Calcium binds to tetracyclines in the gut.

Likelihood Probable Evidence C
Thiazide Diuretics

Taking calcium along with thiazides might increase the risk of hypercalcemia and renal failure.
Thiazides reduce calcium excretion by the kidneys. Using thiazides along with moderately large amounts of calcium carbonate increases the risk of milk-alkali syndrome (hypercalcemia, metabolic alkalosis, renal failure). Patients may need to have their serum calcium levels and/or parathyroid function monitored regularly.

Likelihood Probable Evidence C
Verapamil (Calan, Others)

Theoretically, calcium may reduce the therapeutic effects of verapamil.
Hypercalcemia can reduce the effectiveness of verapamil in atrial fibrillation. Theoretically, use of calcium supplements may increase this risk of hypercalcemia and reduce the effectiveness of verapamil.

Likelihood Probable Evidence D
Calcium Channel Blockers

Intravenous calcium may decrease the effects of calcium channel blockers; oral calcium is unlikely to have this effect.
Intravenous calcium is used to decrease the effects of calcium channel blockers in the management of overdose. Intravenous calcium gluconate has been used before intravenous verapamil (Isoptin) to prevent or reduce the hypotensive effects without affecting the antiarrhythmic effects. But there is no evidence that dietary or supplemental calcium when taken orally interacts with calcium channel blockers.

Likelihood Unlikely Evidence D
Calcium full monograph & interactions

Elderberry Fruit Extract2 drug types · 121 drugs

Immunosuppressants

Theoretically, elderberry might interfere with immunosuppressant therapy due to its immunostimulant activity.
Elderberry has immunostimulant activity, increasing the production of cytokines, including interleukin and tumor necrosis factor.

Likelihood Possible Evidence B
Pazopanib (Votrient)

Theoretically, elderberry might interact with pazopanib, potentially increasing the risk of adverse effects.
In one case, a 65-year-old patient taking pazopanib for 4 weeks for soft-tissue sarcoma developed severe nausea, loose stools, and elevated alanine transaminase and aspartate transaminase levels and was diagnosed with grade 3 liver injury. The patient reported taking elderberry supplements for 2 years, dose unspecified, and was also taking a multivitamin and a calcium supplement. The patient's symptoms and liver enzyme levels improved upon discontinuation of pazopanib and all supplements. Pazopanib treatment was re-initiated, at a lower dose, with no further evidence of liver injury. It was unclear in this case report if the elderberry supplements were derived from the berry, the flower, or the combination.

Likelihood Possible Evidence D
Elderberry Fruit Extract full monograph & interactions

Eyebright, Powder1 drug type · 86 drugs

Antidiabetes Drugs

Theoretically, eyebright might increase the risk of hypoglycemia when taken with antidiabetes drugs.
Animal research suggests that eyebright lowers blood glucose levels.

Likelihood Possible Evidence D
Eyebright, Powder full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Bilberry with Eyebright & Elderberry, from the product label.

Windmill Natural Vitamins

See all Windmill Natural Vitamins products
Name
Windmill Health Products
Street Address
10 Henderson Drive
City
West Caldwell
State
NJ
ZipCode
07006
Web Address
www.windmillvitamins.com
Pharmacist Counseling Corner

Bilberry with Eyebright & Elderberry by Windmill Natural Vitamins: Common Questions

Does Bilberry with Eyebright & Elderberry by Windmill Natural Vitamins interact with any medications?
Yes. Based on its ingredients, Bilberry with Eyebright & Elderberry has a known interaction with 556 medications, including 7 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Bilberry with Eyebright & Elderberry contains 5 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.
Will this help my vision?
Bilberry and eyebright are traditional eye herbs, but the evidence we hold is limited or insufficient to say whether they actually work for vision, age-related eye disease, or other eye conditions. Talk with your doctor about whether this is the right choice for your specific eye health goal.
What are the most common side effects?
From calcium: belching, constipation, diarrhea, gas, and stomach upset. From bilberry: dark stools, gas, and possible tongue or tooth discoloration. Eyebright can cause headache, nausea, and constipation. Most adverse effects are mild and digestive.
Is it safe to take while pregnant or breastfeeding?
Calcium is likely safe in pregnancy and lactation at recommended amounts. Bilberry is likely safe in pregnancy and lactation. However, eyebright and elderberry supplements should be avoided during pregnancy and while breastfeeding due to insufficient safety data. Talk with your doctor or pharmacist before taking this product if you're pregnant or nursing.
Can I take this with my thyroid medication?
Calcium can interfere with how your body absorbs levothyroxine (Synthroid) and similar thyroid drugs. You'd need to space the doses at least 4 hours apart. Check with your doctor or pharmacist to make sure this product is safe with your specific medication and dosing schedule.
What if I take blood thinners or diabetes medication?
Bilberry might theoretically increase bleeding risk with blood thinners and raise the risk of low blood sugar with diabetes drugs. Eyebright also has a theoretical low-blood-sugar interaction. Before starting this product, confirm with your doctor or pharmacist that it's safe with your current medications.
Is there a risk of liver problems from the elderberry?
Properly prepared elderberry from ripe fruit is generally well tolerated. One rare case report linked elderberry to liver injury in a patient with an underlying autoimmune disease who took it for years; this is not common but worth knowing about. If you have liver disease or take medications affecting the liver, discuss this product with your doctor first.

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

Not sure if Bilberry with Eyebright & Elderberry 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 with Eyebright & Elderberry label
Go deeper

The Full Monographs Behind Bilberry with Eyebright & Elderberry’s Ingredients

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

Herb & supplement monograph

Calcium

Interacts with 168 drugs

Calcium is an essential mineral your body needs for strong bones, nerve signaling, and muscle function, and supplements can help fill gaps when diet falls short. Most people do best getting...

Read the full Calcium monograph → Herb & supplement monograph

Eyebright

Interacts with 86 drugs

Eyebright is a traditional herb long used for minor eye irritation, redness, and allergy symptoms, but high-quality human studies are very limited. There is not enough reliable evidence to c...

Read the full Eyebright monograph → Herb & supplement monograph

Elderberry

Interacts with 121 drugs

Elderberry is a popular herbal supplement, mainly taken to help with colds and flu. Some small studies suggest it may modestly shorten cold or flu symptoms, but the evidence is limited and n...

Read the full Elderberry monograph → 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 with Eyebright & Elderberry'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 86 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.

Calcium 62 references
  1. Shils M, Olson A, Shike M. Modern Nutrition in Health and Disease. 8th ed. Philadelphia, PA: Lea and Febiger, 1994.
  2. Hernandez-Avila M, Gonzalez-Cossio T, Hernandez-Avila JE, et al. Dietary calcium supplements to lower blood lead levels in lactating women: a randomized placebo-controlled trial. Epidemiology 2003;14:206-12.. PubMed
  3. Thys-Jacobs S, Ceccarelli S, Bierman A, et al. Calcium supplementation in premenstrual syndrome: a randomized crossover trial. J Gen Intern Med 1989;4:183-9. PubMed
  4. Maton PN, Burton ME. Antacids revisited: a review of their clinical pharmacology and recommended therapeutic use. Drugs 1999;57:855-70.
  5. Clemens JD, Feinstein AR. Calcium carbonate and constipation: a historical review of medical mythopoeia. Gastroenterology 1977;72:957-61. DOI
  6. Saunders D, Sillery J, Chapman R. Effect of calcium carbonate and aluminum hydroxide on human intestinal function. Dig Dis Sci 1988;33:409-13. PubMed
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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.

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