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Dietary supplement

K2 100 mcg Ingredients & Drug Interactions

by Nature Made

K2 100 mcg label
See full label image
Softgel Capsule Category: Vitamin
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 9, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking K2 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

K2 100 mcg is a dietary supplement by Nature Made 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 K2. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against K2 100 mcg by Nature Made

Ask about any prescription or over-the-counter medication and we check it for interactions with K2 100 mcg by Nature Made — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of K2 100 mcg by Nature Made

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 Aug 13, 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: vitamin K2 at 100 micrograms per softgel. Vitamin K2 is a fat-soluble vitamin that plays a role in blood clotting and bone mineralization.

The softgel also contains soybean oil, gelatin, glycerin, water, and carmine as inactive ingredients — these are the capsule and carrier materials that hold the vitamin.

Does it work?

Moderate 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
Moderate

Some clinical evidence supports this product's ingredients for its stated purpose, but it isn't conclusive.

Why this rating?
  • The label markets this product for: helps support healthy bones.
  • We looked for evidence on: Osteoporosis, Bone density, Bone strength, Fracture prevention.
  • The strongest evidence on file: Vitamin K is rated "Possibly Effective" for Osteoporosis (Natural Medicines).

Vitamin K2 is rated effective for conditions involving vitamin K deficiency and clotting problems — including low prothrombin (a clotting protein), vitamin K–dependent clotting factor deficiency, and hemorrhagic disease (bleeding disorders). For osteoporosis, the evidence is rated possibly effective, meaning there's some promise but the data isn't conclusive yet.

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 most people. The most common side effects are mild: nausea, diarrhea, stomach upset, and abdominal pain — these occur in a small number of users.

The safety notes advise that normal dietary amounts are fine, but you should check with your doctor before taking supplements. This product 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.

If you take warfarin (Coumadin) or any other blood thinner (anticoagulant), check with your doctor or pharmacist before taking this product — vitamin K2 can reduce its effectiveness. This is the only medication type with documented interactions in our data for this ingredient.

Check your own medication Run your meds through the checker above

The bottom line

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

K2 is a straightforward way to get vitamin K2 if you need it for clotting or bone health and your doctor agrees. If you're on warfarin or another blood thinner, do not take this without talking to your prescriber first — vitamin K can interfere with how those drugs work.

Check with your own doctor or pharmacist before starting, especially if you take any anticoagulants.

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 Dec 13, 2022.

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 K2 100 mcg, straight from the product label.

Brand Nature Made
Net contents 0 Not Present
Market status On market
Date entered into DSLD Dec 13, 2022
DSLD ID 279867
Product type Vitamin
Supplement form Softgel Capsule
Dietary claims / uses Nutrient, All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Gluten Free
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for K2 100 mcg by Nature Made, 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 Softgel(s)
Maximum serving Sizes:
1 Softgel(s)
IngredientAmount% DV
Vitamin K2100 mcg--

Other ingredients: Soybean Oil, Gelatin, Glycerin, Water, Carmine

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.
General Statements

#1 Pharmacist recommended Vitamin & supplement brand

Based on Pharmacy Times Survey of pharmacists recommending Letter Vitamin Supplements.

Seals/Symbols

USP Verified Dietary Supplement

Formula

MK-7 form

Formulation

Helps support healthy bones

USP has tested and verified ingredients, potency and manufacturing process. USP sets official standards for dietary supplements. www.uspverified.org

No synthetic dyes-colors derived from natural sources No artificial flavors Gluten free

FDA Statement of Identity

Dietary Supplement

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.

Suggested/Recommended/Usage/Directions

Suggested Use: Adults, take 1 softgel daily with water and a meal.

Storage

Store tightly closed, in a cool, dry place, out of reach of children.

Precautions

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

Contains: Soy.

Caution: If you are pregnant, nursing, taking medication, have vascular disease or blood clotting issues, consult your physician before use.

Store tightly closed, in a cool, dry place, out of reach of children.

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

See for yourself

K2 100 mcg by Nature Made label

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

K2 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 K2 100 mcg by Nature Made

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

Serving size1 Softgel(s) Dosage formSoftgel Capsule Amounts shown are per serving.

Vitamin K2

Interacts with
2 drugs
100 mcg per serving Form: Menaquinone-7

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 K2 monograph & interactions

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

Interaction report

K2 100 mcg by Nature Made Drug Interactions

Want to check YOUR meds against K2 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 K2 2

Individual Drug Interactions

The ingredients in K2 100 mcg interact with 2 drugs. Click any drug to see the details.

1 of the 1 ingredient in K2 100 mcg interact with drugs. Each result below shows which ingredient is responsible. Vitamin K2

Each ingredient & the kinds of drugs it affects

For each ingredient in K2 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 K21 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 K2 full monograph & interactions
The maker

Brand information

Manufacturer and brand details for K2 100 mcg, from the product label.

Nature Made

See all Nature Made products
Name
Nature Made Nutritional Products
City
West Hills
State
CA
ZipCode
91309-9903
Phone Number
1-800-276-2878
Web Address
www.NatureMade.com
Pharmacist Counseling Corner

K2 100 mcg by Nature Made: Common Questions

Does K2 100 mcg by Nature Made interact with any medications?
Yes. Based on its ingredients, K2 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?
K2 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.
Can I take this if I'm on warfarin?
Not without talking to your doctor first. Vitamin K can work against warfarin and weaken its blood-thinning effect. Your prescriber may need to adjust your warfarin dose or monitor you more closely if you use this supplement.
What are the side effects?
Taken by mouth, vitamin K2 is generally well tolerated. The most common side effects are mild gastrointestinal issues — nausea, diarrhea, stomach upset, and abdominal pain. These occur in a small number of users.
Is it safe to take during pregnancy or breastfeeding?
Yes, vitamin K2 is rated likely safe during pregnancy and lactation. That said, every pregnancy is unique — if you have questions about whether it's right for you, talk with your doctor or midwife.
What does vitamin K2 actually do?
Vitamin K is essential for blood clotting and helps activate proteins that stabilize bone. This product is effective for treating vitamin K deficiency and clotting disorders. It's also possibly effective for osteoporosis, though the evidence isn't as firm.
Is this the same as vitamin K1?
No — this is vitamin K2, a different form of the vitamin. The product facts cover K2 specifically; if you're comparing it to K1 or want to know which form is right for you, talk with your doctor or pharmacist.

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

Not sure if K2 100 mcg is safe with your meds?

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Ask a pharmacist

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.

K2 100 mcg label
Go deeper

The Full Monographs Behind K2 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

K2 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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