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Dietary supplement

Vitamin K2 100 mcg Ingredients & Drug Interactions

by The Vitamin Shoppe

Vitamin K2 100 mcg label
See full label image
Capsule Category: Vitamin
Most serious interaction: Major
Clinical methodology reviewed by · Updated Oct 7, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Vitamin 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

Vitamin K2 100 mcg is a dietary supplement by The Vitamin Shoppe with 2 active ingredients. Its ingredients are commonly taken for bone health and osteoporosis, correcting vitamin d deficiency, immune system support.Based on those ingredients, 717 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Vitamin D3, 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 Vitamin K2 100 mcg by The Vitamin Shoppe

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

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HelloPharmacist Scorecard of Vitamin K2 100 mcg by The Vitamin Shoppe

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 Oct 1, 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 2 of its 2 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

This product contains 2 active ingredients: vitamin D3 and vitamin K2. Vitamin D3 is a fat-soluble form of vitamin D that your body can convert to its active hormone form; it plays a central role in calcium absorption, bone health, and immune function.

Vitamin K2 is a form of vitamin K that supports bone mineralization and blood clotting factors. The capsule also contains microcrystalline cellulose, silicon dioxide, and magnesium stearate as inactive ingredients.

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: Bone and cardiovascular health.
  • We looked for evidence on: Cardiovascular disease (CVD), Osteoporosis, Fractures, Hyperparathyroidism-related bone loss, Corticosteroid-induced osteoporosis, Kidney transplant-related bone loss — and 3 related terms.
  • The strongest evidence on file: Vitamin D is rated "Likely Effective" for Corticosteroid-induced osteoporosis (Natural Medicines).
  • Also on file: Vitamin D is rated "Possibly Effective" for Hyperparathyroidism-related bone loss.
  • Also on file: Vitamin K is rated "Possibly Effective" for Osteoporosis.

Vitamin D3 is effective for treating rickets, osteomalacia (soft bones), familial hypophosphatemia, and renal bone disease. Vitamin K2 is effective for treating bleeding disorders tied to vitamin K deficiency and may be possibly effective for osteoporosis, though the evidence for bone health is not yet established in our data.

If you're considering this product for a specific condition, talk it over with your doctor to see if it's the right choice for your situation.

The evidence, ingredient by ingredient Vitamin D 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 2 of the 2 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 2 of 2.
  • General safety write-ups exist for 2 of 2.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Vitamin D3 is generally well tolerated at recommended doses, but very high doses taken over time can build up and cause toxicity, with symptoms including high blood calcium (hypercalcemia), kidney problems, and bone loss. Vitamin K taken by mouth is generally well tolerated; the most common side effects reported in trials are mild gastrointestinal upset — nausea, stomach pain, and diarrhea — though these are not common.

In pregnancy, vitamin D3 is likely safe at recommended amounts and vitamin K2 is likely safe; however, vitamin D3 may also carry some risk at higher doses and should be used only under your doctor's guidance. For breastfeeding, both are considered likely safe.

If you're pregnant or nursing, discuss the dose with your doctor or pharmacist.

Side effects, ingredient by ingredient Vitamin D 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?
  • 2 of the 2 matched ingredients can interact with medications — Vitamin D, Vitamin K.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; heart-rhythm medications.
  • For scale: 718 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, check with your pharmacist or doctor if you take warfarin or any other blood thinner — vitamin K2 can reduce their effectiveness (Major severity). Also check if you take verapamil, diltiazem, digoxin, atorvastatin, thiazide water pills, calcipotriene skin cream for psoriasis, or aluminum-containing medicines (Moderate severity), or any broad class of drugs metabolized by the liver enzyme CYP3A4 (Minor severity).

Vitamin D can raise your blood calcium and interfere with how these drugs work.

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 two-ingredient product may be worth considering if you need vitamin D and K support and have no interactions with blood thinners or heart medications. If you take warfarin, any calcium-channel blocker, a thiazide diuretic, digoxin, or atorvastatin, you'll need to check your specific situation with your doctor or pharmacist first — vitamin K2 and high-dose vitamin D can be problematic with these drugs.

At recommended doses, both ingredients are generally well tolerated, though vitamin D toxicity is possible with excessive amounts over time.

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

Assessment coverage: 2 of 2 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Nov 21, 2018.

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 K2 100 mcg, straight from the product label.

Brand The Vitamin Shoppe
Barcode (UPC) 766536025589
Net contents 90 Veggie Capsule(s)
Market status On market
Date entered into DSLD Nov 21, 2018
DSLD ID 183800
Product type Vitamin
Supplement form Capsule
Dietary claims / uses Nutrient, All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Gluten Free, Dairy 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 Vitamin K2 100 mcg by The Vitamin Shoppe, 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 Veggie Capsule(s)
Maximum serving Sizes:
1 Veggie Capsule(s)
UPC/BARCODE
766536025589
IngredientAmount% DV
Vitamin D310 mcg50%
Vitamin K2100 mcg83%

Other ingredients: Microcrystalline Cellulose, Vegetable capsule, Silicon Dioxide, 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.
General Statements

Vitamin

Bone Cardiovascular

Visit www.vitaminshoppe.com or call 1-800-223-1216 for more information and to reorder.

FDA Statement of Identity

Dietary Supplement

Formulation

Gluten free Dairy free Soy free Nut free

Dose not contain: Gluten, preservatives, artificial colors or flavors.

Storage

Store in a cool, dry place.

Precautions

Keep out of reach of children.

Tamper evident Do not use if outer seal is broken or missing.

Warning: Consult your healthcare provider prior to use if you are pregnant, nursing, taking any medication or have any medical conditions.

Suggested/Recommended/Usage/Directions

Directions: Take one (1) veggie capsule daily.

Formula

Research indicates that Vitamin K2, as menaquinone-7, minimizes bone loss, helps build bone mass and supports cardiovascular health.

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 disease.

General

Item No. VS-2558 2096394 GS 37

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

See for yourself

Vitamin K2 100 mcg by The Vitamin Shoppe label

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

Vitamin 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 Vitamin K2 100 mcg by The Vitamin Shoppe

These are the 2 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 Veggie Capsule(s) Dosage formCapsule 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.

Vitamin D3

Interacts with
717 drugs
10 mcg per serving Form: Cholecalciferol

Vitamin D is a fat-soluble vitamin that helps your body absorb calcium and is important for healthy bones, muscles, and immune function. Many people,...

Vitamin D3 monograph & interactions

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: Microcrystalline Cellulose, Vegetable capsule, Silicon Dioxide, Magnesium Stearate. These complete the product’s ingredient list but are not active constituents.

Interaction report

Vitamin K2 100 mcg by The Vitamin Shoppe Drug Interactions

Want to check YOUR meds against Vitamin 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
717Drugs
2 Major 80 Moderate 635 Minor

Ingredients driving the most interactions

Vitamin D3 717
Vitamin K2 2

Individual Drug Interactions

The ingredients in Vitamin K2 100 mcg interact with 717 drugs. Click any drug to see the details.

2 of the 2 ingredients in Vitamin K2 100 mcg interact with drugs. Each result below shows which ingredient is responsible. Vitamin D3 Vitamin K2

Each ingredient & the kinds of drugs it affects

For each ingredient in Vitamin K2 100 mcg 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.

Vitamin D38 drug types · 717 drugs

Aluminum

Vitamin D might increase aluminum absorption and toxicity, but this has only been reported in people with renal failure.
The protein that transports calcium across the intestinal wall can also bind and transport aluminum. This protein is stimulated by vitamin D, which may therefore increase aluminum absorption. This mechanism may contribute to increased aluminum levels and toxicity in people with renal failure, when they take vitamin D and aluminum-containing phosphate binders chronically.

Likelihood Probable Evidence B
Atorvastatin (Lipitor)

Vitamin D might reduce absorption of atorvastatin.
A small, low-quality clinical study shows that taking vitamin D reduces levels of atorvastatin and its active metabolites by up to 55%. However, while atorvastatin levels decreased, total cholesterol, low-density lipoprotein (LDL) cholesterol, and high-density lipoprotein (HDL) cholesterol levels did not substantially change. Atorvastatin is metabolized in the gut by CYP3A4 enzymes, and researchers theorized that vitamin D might induce CYP3A4, causing reduced levels of atorvastatin. However, this proposed mechanism was not specifically studied.

Likelihood Probable Evidence B
Calcipotriene (Dovonex)

Taking calcipotriene with vitamin D increases 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 vitamin D supplements might increase the risk of hypercalcemia.

Likelihood Probable Evidence D
Digoxin (Lanoxin)

Theoretically, hypercalcemia induced by high-dose vitamin D can increase the risk of arrhythmia from digoxin.
High doses of vitamin D can cause hypercalcemia. Hypercalcemia increases the risk of fatal cardiac arrhythmias with digoxin. Avoid vitamin D doses above the tolerable upper intake level (4000 IU daily for adults) and monitor serum calcium levels in people taking vitamin D and digoxin concurrently.

Likelihood Possible Evidence D
Diltiazem (Cardizem, Others)

Theoretically, hypercalcemia induced by high-dose vitamin D can reduce the therapeutic effects of diltiazem for arrhythmia.
High doses of vitamin D can cause hypercalcemia. Hypercalcemia can reduce the effectiveness of verapamil in atrial fibrillation. Theoretically this could also occur with diltiazem. Avoid vitamin D doses above the tolerable upper intake level (4000 IU daily for adults) and monitor serum calcium levels in people taking vitamin D and diltiazem concurrently.

Likelihood Probable Evidence B
Thiazide Diuretics

Theoretically, taking thiazide diuretics and high-dose vitamin D can increase the risk of hypercalcemia.
Thiazide diuretics decrease urinary calcium excretion, which could lead to hypercalcemia if vitamin D supplements are taken concurrently. This has been reported in people being treated with vitamin D for hypoparathyroidism, and also in elderly people with normal parathyroid function who were taking a thiazide, vitamin D, and calcium-containing antacids daily.

Likelihood Probable Evidence D
Verapamil (Calan, Others)

Hypercalcemia induced by high-dose vitamin D can reduce the therapeutic effects of verapamil for arrhythmia.
Hypercalcemia due to high doses of vitamin D can reduce the effectiveness of verapamil in atrial fibrillation. Avoid vitamin D doses above the tolerable upper intake level (4000 IU daily for adults) and monitor serum calcium levels in people taking vitamin D and verapamil concurrently.

Likelihood Probable Evidence B
Cytochrome P450 3A4 (Cyp3A4) Substrates

Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.
There is some concern that vitamin D might induce CYP3A4. In vitro research suggests that vitamin D induces CYP3A4 transcription. Additionally, observational research has found that increased UV light exposure and serum vitamin D levels are associated with decreased serum levels of CYP3A4 substrates such as tacrolimus and sirolimus, while no association between UV light exposure or vitamin D levels and levels of mycophenolic acid, a non-CYP3A4 substrate, was found. A small, low-quality clinical study shows that taking vitamin D reduces levels of the CYP3A4 substrate atorvastatin and its active metabolites by up to 55%; however, the clinical effects of atorvastatin were not reduced. While researchers theorized that vitamin D might induce CYP3A4, this proposed mechanism was not specifically studied.

Likelihood Possible Evidence D
Vitamin D3 full monograph & interactions

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 Vitamin K2 100 mcg, from the product label.

The Vitamin Shoppe

See all The Vitamin Shoppe products
Name
Vitamin Shoppe, Inc.
City
Secaucus
State
NJ
ZipCode
07094
Phone Number
1-800-223-1216
Web Address
www.vitaminshoppe.com
Pharmacist Counseling Corner

Vitamin K2 100 mcg by The Vitamin Shoppe: Common Questions

Does Vitamin K2 100 mcg by The Vitamin Shoppe interact with any medications?
Yes. Based on its ingredients, Vitamin K2 100 mcg has a known interaction with 717 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 K2 100 mcg contains 2 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 interfere with my warfarin?
Yes — vitamin K2 in this product can reduce warfarin's blood-thinning effect. Do not take this without checking with your doctor or pharmacist first, as it may increase your clot risk.
What are the most common side effects?
Vitamin K taken by mouth may cause mild stomach upset — nausea, abdominal pain, or diarrhea — though these are not common. Vitamin D at recommended doses is generally well tolerated; excessive doses are what cause problems like high blood calcium.
Can I take this while pregnant?
Vitamin D3 is likely safe at recommended doses during pregnancy, and vitamin K2 is likely safe; however, vitamin D carries some safety concerns at higher doses. Talk with your doctor about the right dose for you before taking this product.
Can I breastfeed while taking this?
Yes — both vitamin D3 and vitamin K2 are considered likely safe during breastfeeding at the amounts found in this product.
Is there a reason I might have high blood calcium already?
If you take certain diuretics, digoxin, or have kidney problems, vitamin D can raise your blood calcium more easily. Talk with your doctor or pharmacist to make sure this product is right for you.
Does this product have any fillers?
Yes — it contains microcrystalline cellulose, silicon dioxide, and magnesium stearate as inactive ingredients to make the capsule.

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

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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 K2 100 mcg label
Go deeper

The Full Monographs Behind Vitamin 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 D

Interacts with 717 drugs

Vitamin D is a fat-soluble vitamin that helps your body absorb calcium and is important for healthy bones, muscles, and immune function. Many people, especially those with low sun exposure,...

Read the full Vitamin D monograph → 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 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 37 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 D 25 references
  1. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
  2. Tatro DS, ed. Drug Interactions Facts. Facts and Comparisons Inc., St. Louis, MO. 1999.
  3. Koutkia P, Chen TC, Holick MF. Vitamin D intoxication associated with an over-the-counter supplement. N Engl J Med 2001;345:66-7. PubMed
  4. Bar-Or D, Yoel G. Calcium and calciferol antagonize effect of verapamil in atrial fibrillation. Br Med J 1981;282:1585-6.
  5. Demontis R, Leflon A, Fournier A, et al. 1 alpha(OH) vitamin D3 increases plasma aluminum in hemodialyzed patients taking AI(OH)3. Clin Nephrol 1986;26:146-9.
  6. Crowe M, Wollner L, Griffiths RA. Hypercalcemia following vitamin D and thiazide therapy in the elderly. Practitioner 1984;228:312-3.
  7. Parfitt AM. Thiazide-induced hypercalcemia in vitamin D-treated hypoparathyroidism. Ann Intern Med 1972;77:557-63. PubMed
  8. Thiazide diuretics and the risk of osteoporosis. Pharmacist's Letter/Prescriber's Letter 2003;19(11):191105.
  9. Moon J. The role of vitamin D in toxic metal absorption. J Am Coll Nutr 1994;13:559-64.
  10. Demontis R, Reissi D, Noel C, et al. Indirect clinical evidence that 1alphaOH vitamin D<SUB>3</SUB> increases the intestinal absorption of aluminum. Clin Nephrol 1989;31:123-7.
  11. Adler AJ, Berlyne GM. Duodenal aluminum absorption in the rat: effect of vitamin D. Am J Physiol 1985;249:G209-13. PubMed
  12. Schwartz JB. Effects of vitamin D supplementation in atorvastatin-treated patients: A new drug interaction with an unexpected consequence. Clin Pharmacol Ther 2009;85:198-203. PubMed
  13. Dietary reference intakes for calcium and vitamin D. Institute of Medicine, November 30, 2010. Available at: http://www.iom.edu/~/media/Files/Report%20Files/2010/Dietary-Reference-Intakes-for-Calcium-and-Vitamin-D/Vitamin%20D%20and%20Calcium%202010%20Repo
  14. Cox KA, Dunn MA. Aluminum toxicity alters the regulation of calbindin-D28k protein and mRNA expression in chick intestine. J Nutr 2001;131:2007-13. PubMed
  15. Escribano, J., Balaguer, A., Pagone, F., Feliu, A., and Roque, I. Figuls. Pharmacological interventions for preventing complications in idiopathic hypercalciuria. Cochrane.Database.Syst.Rev. 2009;(1):CD004754. PubMed
  16. Carlton, S., Clopton, D., and Cappuzzo, K. A. Vitamin D deficiency: appropriate replenishment therapies and the effects of vitamin D toxicity. Consult Pharm 2010;25(3):171-177. PubMed
  17. Wang, H., Xia, N., Yang, Y., and Peng, D. Q. Influence of vitamin D supplementation on plasma lipid profiles: a meta-analysis of randomized controlled trials. Lipids Health Dis. 2012;11:42. PubMed
  18. Turner AN, Carr Reese P, Fields KS, Anderson J, Ervin M, Davis JA, Fichorova RN, Roberts MW, Klebanoff MA, Jackson RD. A blinded, randomized controlled trial of high-dose vitamin D supplementation to reduce recurrence of bacterial vaginosis. Am J Obstet G PubMed
  19. Weiner M, Epstein FH. Signs and symptoms of electrolyte disorders. Yale J Biol Med. 1970;43(2):76-109.
  20. Lappe J, Watson P, Travers-Gustafson D, Recker R, Garland C, Gorham E, Baggerly K, McDonnell SL. Effect of Vitamin D and Calcium Supplementation on Cancer Incidence in Older Women: A Randomized Clinical Trial. JAMA. 2017 Mar 28;317(12):1234-1243. PubMed
  21. Roth DE, Leung M, Mesfin E, Qamar H, Watterworth J, Papp E. Vitamin D supplementation during pregnancy: state of the evidence from a systematic review of randomised trials. BMJ. 2017;359:j5237. PubMed
  22. Murai IH, Fernandes AL, Sales LP, et al. Effect of a single high dose of vitamin D3 on hospital length of stay in patients with moderate to severe COVID-19: A randomized clinical trial. JAMA. 2021.
  23. Wang Z, Schuetz EG, Xu Y, Thummel KE. Interplay between vitamin D and the drug metabolizing enzyme CYP3A4. J Steroid Biochem Mol Biol 2013;136:54-8. PubMed
  24. Doyle D, Browne U, Brickley A, Murphy D. Vitamin D-induced hypercalcaemia and acute kidney injury in sarcoidosis. BMJ Case Rep 2023;16(1):e250580. PubMed
  25. Williamson A, Martineau AR, Sheikh A, Jolliffe D, Griffiths CJ. Vitamin D for the management of asthma. Cochrane Database Syst Rev 2023;2(2):CD011511. PubMed

See these in context on the Vitamin D monograph →

Vitamin K 12 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. Stevenson, M., Lloyd-Jones, M., and Papaioannou, D. Vitamin K to prevent fractures in older women: systematic review and economic evaluation. Health Technol.Assess. 2009;13(45):iii-134. PubMed
  10. 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.
  11. 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
  12. 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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