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Dietary supplement

Vitamin K 100 mcg Ingredients & Drug Interactions

by Vitamin World

Vitamin K 100 mcg label
See full label image
Tablet Or Pill Category: Vitamin
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 30, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Vitamin K 100 mcg 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

Vitamin K 100 mcg is a dietary supplement by Vitamin World with 1 active ingredient. Its ingredients are commonly taken for supporting normal blood clotting, bone health, heart and vascular health.Based on those ingredients, 2 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Vitamin K. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Vitamin K 100 mcg by Vitamin World

Ask about any prescription or over-the-counter medication and we check it for interactions with Vitamin K 100 mcg by Vitamin World — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Vitamin K 100 mcg by Vitamin World

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 Sep 24, 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 1 active ingredient: vitamin K, a fat-soluble nutrient that plays a central role in blood clotting and bone health. Vitamin K activates special proteins that help your blood form clots when you bleed and may support bone strength.

The tablet also contains inactive ingredients—dicalcium phosphate, vegetable cellulose, stearic acid, and vegetable magnesium stearate—which are fillers, binders, and lubricants that hold the tablet together.

Does it work?

Strong evidence
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
Strong

Clinical evidence supports at least one of this product's ingredients for its stated purpose.

Why this rating?
  • The label markets this product for: vitamin K support for blood clotting and bone health.
  • We looked for evidence on: Hemorrhagic disease, Hypoprothrombinemia, Vitamin K-dependent clotting factors deficiency (VKCFD), Warfarin anticoagulation, Osteoporosis, Cardiovascular disease (CVD) — and 3 related terms.
  • The strongest evidence on file: Vitamin K is rated "Effective" for Hemorrhagic disease (Natural Medicines).
  • Also on file: Vitamin K is rated "Effective" for Hypoprothrombinemia, Warfarin anticoagulation, Vitamin K-dependent clotting factors deficiency (VKCFD).
  • Also on file: Vitamin K is rated "Possibly Effective" for Osteoporosis.

The data shows vitamin K is effective for preventing and treating vitamin K deficiency bleeding (hypoprothrombinemia) and for correcting low vitamin K–dependent clotting factors. It is also effective for managing anticoagulation when warfarin therapy requires adjustment.

For bone strength and osteoporosis, vitamin K has possibly effective evidence—meaning some research suggests it may help, but more data is needed to be certain.

The evidence, ingredient by ingredient Vitamin K

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.

Taken by mouth, vitamin K is generally well tolerated in healthy people at normal dietary amounts and in most supplements. The most common side effects are mild: diarrhea, nausea, and stomach upset.

Serious adverse effects from oral doses are rare. However, because of its interaction with warfarin, you should check with your doctor before taking a supplement—dietary amounts are fine, but supplements warrant a conversation with your provider.

Vitamin K is rated likely safe in pregnancy and lactation.

Side effects, ingredient by ingredient Vitamin K

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?
  • 1 of the 1 matched ingredient can interact with medications — Vitamin K.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs.
  • For scale: 2 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.

Warfarin (Coumadin) and related blood thinners (anticoagulants) are the main concern—Major severity. Vitamin K can reduce how well they work.

Check any blood thinner you're on with your doctor or pharmacist before starting this product.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with clinical evidence supporting its stated purpose. Major medication interactions have been identified, and safety information is well characterized.

This supplement is straightforward for people who aren't on blood thinners—vitamin K supports clotting and possibly bone health with a good safety profile. If you take warfarin or another blood thinner, do not start this without talking to your doctor first; vitamin K can interfere with how well your medication works.

Either way, confirm with your own doctor or pharmacist before adding it to your routine.

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 Oct 26, 2011.

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 Vitamin K 100 mcg, straight from the product label.

Brand Vitamin World
Barcode (UPC) 074312730702
Net contents 100 Tablet(s)
Market status On market
Date entered into DSLD Oct 26, 2011
DSLD ID 875
Product type Vitamin
Supplement form Tablet Or Pill
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Vegetarian, 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 Vitamin K 100 mcg by Vitamin World, 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)
UPC/BARCODE
074312730702
IngredientAmount% DV
Vitamin K100 mcg125%

Other ingredients: Dicalcium Phosphate, Vegetable Cellulose, Stearic Acid, Vegetable Magnesium Stearate

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.
Brand IP Statement(s)

© 2009 Vitamin World, Inc

FDA Disclaimer Statement

*This statement has not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

Formulation

No Artificial Color or Flavor, No Preservatives, No Sugar, No Starch, No Milk, No Lactose, No Soy, No Gluten, No Wheat, No Yeast, No Fish. Sodium Free.

VEGETARIAN DIETARY SUPPLEMENT

Precautions

Do not use if seal under cap is broken or missing.

WARNING: If you are pregnant, nursing or taking any medication, consult your doctor before use. Discontinue use and consult your doctor if any adverse reactions occur. Keep out of reach of children.

Storage

Store in a cool, dry place.

General

PROD. #3070 B3070 05D

General Statements

BONE & JOINT HEALTH*

Synergistic Companion to Calcium & Vitamin D

This product has been developed, manufactured and packaged by Vitamin World. Our world-class facilities allow us to control exactly what goes into each product. It is your assurance that you are getting the highest quality and freshest products. Yout have our guarantee!

Vitamin K is necessary for the formation of prothrombin, which is required for normal blood clotting.* Vitamin K is also a great companion to Calcium and Vitamin D supplements.

Get healthy.

Seals/Symbols

QUALITY ASSURED

Suggested/Recommended/Usage/Directions

DIRECTIONS: For adults, take one (1) tablet daily, preferably with a meal.

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

See for yourself

Vitamin K 100 mcg by Vitamin World label

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

Vitamin K 100 mcg 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 Vitamin K 100 mcg by Vitamin World

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

Serving size1 Tablet(s) Dosage formTablet Or Pill Amounts shown are per serving.

Vitamin K

Interacts with
2 drugs
100 mcg per serving Form: Phytonadione

Vitamin K is an essential nutrient your body needs for normal blood clotting and to support healthy bones. Most people get enough from food, but suppl...

Vitamin K monograph & interactions

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

Interaction report

Vitamin K 100 mcg by Vitamin World Drug Interactions

Want to check YOUR meds against Vitamin K 100 mcg?

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
2Drugs
2 Major

Ingredients driving the most interactions

Vitamin K 2

Individual Drug Interactions

The ingredients in Vitamin K 100 mcg interact with 2 drugs. Click any drug to see the details.

1 of the 1 ingredient in Vitamin K 100 mcg interact with drugs. Each result below shows which ingredient is responsible. Vitamin K

Each ingredient & the kinds of drugs it affects

For each ingredient in Vitamin K 100 mcg 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.

Vitamin K1 drug type · 2 drugs

Warfarin (Coumadin)

Vitamin K can antagonize and reverse the therapeutic effects of warfarin.
Vitamin K antagonizes the effects of warfarin. Excessive vitamin K intake, either from supplements or from changes in the diet, can reduce the anticoagulant effect of warfarin.

Likelihood Likely Evidence C
Vitamin K full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Vitamin K 100 mcg, from the product label.

Vitamin World

See all Vitamin World products
Phone Number
1-800-228-4533
Web Address
www.vitaminworld.com
Pharmacist Counseling Corner

Vitamin K 100 mcg by Vitamin World: Common Questions

Does Vitamin K 100 mcg by Vitamin World interact with any medications?
Yes. Based on its ingredients, Vitamin K 100 mcg has a known interaction with 2 medications, including 2 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Vitamin K 100 mcg 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.
Will this vitamin K interfere with my warfarin?
Yes—vitamin K directly reduces warfarin's effect. Even small increases in vitamin K intake can weaken the blood thinner's ability to prevent clots. Do not start this supplement without clearing it with your doctor first; your anticoagulation depends on keeping vitamin K intake stable and predictable.
What are the side effects of taking vitamin K?
Taken by mouth, vitamin K is generally well tolerated. The most common side effects are mild: diarrhea, nausea, and stomach upset. Serious adverse effects from oral supplements are rare.
Is vitamin K safe during pregnancy or breastfeeding?
Yes—vitamin K is rated likely safe during pregnancy and lactation. That said, it's always wise to mention any supplement you're considering to your doctor during pregnancy or while nursing.
What does vitamin K actually do in my body?
Vitamin K activates proteins that help your blood form clots when you bleed and may support bone strength. It's essential for normal blood clotting and is being studied for bone health.
Do I need a supplement, or is dietary vitamin K enough?
Normal dietary amounts of vitamin K are fine for most healthy people. The data shows you should check with your doctor before taking a supplement—especially if you're on any medications.

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

Not sure if Vitamin K 100 mcg 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.

Vitamin K 100 mcg label
Go deeper

The Full Monographs Behind Vitamin K 100 mcg’s Ingredients

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

Herb & supplement monograph

Vitamin K

Interacts with 2 drugs

Vitamin K is an essential nutrient your body needs for normal blood clotting and to support healthy bones. Most people get enough from food, but supplements are sometimes used for deficiency...

Read the full Vitamin K monograph →
Sources

Sources & How We Checked

Vitamin K 100 mcg'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 11 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.

Vitamin K 11 references
  1. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
  2. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc. Washington, DC: National Academy Press, 2002.
  3. Crowther MA, Ageno W, Garcia D, et al. Oral vitamin K versus placebo to correct excessive anticoagulation in patients receiving warfarin: a randomized trial. Ann Intern Med. 2009;150(5):293-300. PubMed
  4. Dietary vitamin K guidance: an effective strategy for stable control of oral anticoagulation? Nutr Rev. 2010;68(3):178-81. PubMed
  5. Kim JS, Nafziger AN, Gaedigk A, et al. Effects of oral vitamin K on S- and R-warfarin pharmacokinetics and pharmacodynamics: enhanced safety of warfarin as a CYP2C9 probe. J Clin Pharmacol. 2001 Jul;41(7):715-22. PubMed
  6. Riegert-Johnson, D. L. and Volcheck, G. W. The incidence of anaphylaxis following intravenous phytonadione (vitamin K1): a 5-year retrospective review. Ann.Allergy Asthma Immunol. 2002;89(4):400-406. PubMed
  7. Dezee, K. J., Shimeall, W. T., Douglas, K. M., Shumway, N. M., and O'malley, P. G. Treatment of excessive anticoagulation with phytonadione (vitamin K): a meta-analysis. Arch.Intern.Med. 2-27-2006;166(4):391-397. DOI
  8. Dentali, F., Ageno, W., and Crowther, M. Treatment of coumarin-associated coagulopathy: a systematic review and proposed treatment algorithms. J.Thromb.Haemost. 2006;4(9):1853-1863. PubMed
  9. Caluwé R, Vandecasteele S, Van Vlem B, Vermeer C, De Vriese AS. Vitamin K2 supplementation in haemodialysis patients: a randomized dose-finding study. Nephrol Dial Transplant. 2014;29(7):1385-90.
  10. Huang ZB, Wan SL, Lu YJ, Ning L, Liu C, Fan SW. Does vitamin K2 play a role in the prevention and treatment of osteoporosis for postmenopausal women: a meta-analysis of randomized controlled trials. Osteoporos Int. 2015;26(3):1175-86. PubMed
  11. Hunnali CR, Devi U, Kitchanan S, Sethuraman G. Three Different Regimens for Vitamin K Birth Prophylaxis in Infants Born Preterm: A Randomized Clinical Trial. J Pediatr 2023;255:98-104. PubMed

See these in context on the Vitamin K 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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