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Dietary supplement

Vitamin D3 & K2 Ingredients & Drug Interactions

by aSquared Nutrition

Vitamin D3 & K2 label
See full label image
Tablet Or Pill Category: Vitamin
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 23, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Vitamin D3 & K2 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 D3 & K2 is a dietary supplement by aSquared Nutrition 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, 715 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 D3 & K2 by aSquared Nutrition

Ask about any prescription or over-the-counter medication and we check it for interactions with Vitamin D3 & K2 by aSquared Nutrition — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Vitamin D3 & K2 by aSquared Nutrition

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

This product has 2 active ingredients: Vitamin D3 and Vitamin K2. Vitamin D3 helps your body absorb calcium and is used to treat conditions like rickets, osteomalacia (soft bones), and certain types of low phosphate or parathyroid disorders.

Vitamin K2 supports blood clotting and bone health; it's used for clotting factor deficiency and shows some promise for osteoporosis. The tablet also contains several inactive ingredients (dextrose, cherry flavor, stearic acid, magnesium stearate, citric acid, and silicon dioxide) as binders and fillers.

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 health and vitamin D supplementation.
  • We looked for evidence on: Osteoporosis, Fractures, Fall prevention, Corticosteroid-induced osteoporosis, Hyperparathyroidism-related bone loss, Kidney transplant-related bone loss — and 4 related terms.
  • The strongest evidence on file: Vitamin D is rated "Effective" for Osteomalacia (Natural Medicines).
  • Also on file: Vitamin D is rated "Likely Effective" for Corticosteroid-induced osteoporosis.
  • Also on file: Vitamin D is rated "Possibly Effective" for Hyperparathyroidism-related bone loss.

Vitamin D3 is well established for treating rickets, osteomalacia, renal bone disease, and familial hypophosphatemia—these uses are rated effective. Vitamin K2 is effective for vitamin K-dependent clotting factor deficiency and hemorrhagic disease, and it shows some promise for osteoporosis, though the evidence for bone health is rated possibly effective rather than proven.

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 over time can cause toxicity—symptoms include high calcium levels in the blood, along with rare cases of bone loss in adults and slowed growth in children. Vitamin K2 taken by mouth is also generally well tolerated; mild gastrointestinal side effects like nausea, stomach upset, and diarrhea can occur but are uncommon.

Vitamin D3 is likely safe in pregnancy at recommended amounts and acceptable during breastfeeding, though check with your doctor about higher doses. Vitamin K2 is considered likely safe during both pregnancy and breastfeeding at normal dietary amounts, but use only under medical guidance.

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: 716 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 or any blood thinner, do not take this product without checking with your doctor—vitamin K2 can reverse warfarin's effects. If you take thiazide water pills, calcium channel blockers for heart rhythm (like verapamil or diltiazem), digoxin, atorvastatin, calcipotriene cream for psoriasis, or aluminum-containing products, flag this supplement with your doctor or pharmacist before starting.

If you take medications processed through the CYP3A4 enzyme pathway, mention this product as well.

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 combination might be worth considering if you're trying to support bone health and your doctor thinks you need both vitamins—but the warfarin interaction is a dealbreaker if you take that blood thinner, and the vitamin D interactions with heart, kidney, and cholesterol medications are serious enough that you need to clear this with your doctor or pharmacist first. Talk it over with your own healthcare provider before you start.

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 May 19, 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 Vitamin D3 & K2, straight from the product label.

Brand aSquared Nutrition
Barcode (UPC) 641799787453
Net contents 180 Chewable Tablet(s)
Market status On market
Date entered into DSLD May 19, 2022
DSLD ID 264075
Product type Vitamin
Supplement form Tablet Or Pill
Dietary claims / uses Nutrient, All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years)
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for Vitamin D3 & K2 by aSquared Nutrition, 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
180
UPC/BARCODE
641799787453
IngredientAmount% DV
Vitamin D32000 IU500%
Vitamin K275 mcg94%

Other ingredients: Dextrose, natural Cherry flavor, Stearic Acid, Magnesium Stearate, Citric Acid, Silicon Dioxide

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

Suggested Use: 1 tablet taken 1 to 3 times daily preferably with meals or as directed by a healthcare professional. For best results, chew tablet thoroughly before swallowing.

Precautions

Caution: Do not exceed recommended dose.

Pregnant or nursing mothers, children under 18 years of age, individuals taking anti-coagulant drugs, such as Coumadin/warfarin, and individuals with a known medical condition should consult a health care professional before using this or any dietary supplement.

Pregnant or nursing mothers, children under 18 years of age, individuals taking anti-coagulant drugs, such as Coumadin/warfarin, and individuals with a known medical condition should consult a health care professional before using this or any dietary supplement.

This product is manufactured and packaged in a facility which may also process milk, soy, wheat, egg, peanuts, tree nuts, fish and crustacean shellfish.

Keep out of reach of children.

Do not use if safety seal is damaged or missing.

Allergen Warning: Contains soy.

Storage

Store in a cool, dry place.

Seals/Symbols

Sourced from a GMP Certified Facility Good Manufacturing Practice Quality Assured

Made in the USA

General Statements

Please recycle.

Unique formula 180 tablets

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.

Formulation

Max strength Supports bone density & calcium absorption Supports cardiovascular & brain health Supports immune system health

Non-GMO formula High quality Great taste

FDA Statement of Identity

Dietary Supplement

Formula

aSquared Nutrition is proud to offer a vitamin D-3 & K-2 (MK7) combination supplement that contains 2000 IU of Vitamin D3 per tablet. Our chewable tablet formula helps support bone density and calcium absorption in the body. It also helps support cardiovascular health and cognitive function.

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

See for yourself

Vitamin D3 & K2 by aSquared Nutrition label

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

Vitamin D3 & K2 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 D3 & K2 by aSquared Nutrition

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

Serving size1 Tablet(s) Dosage formTablet Or Pill Servings per container180 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
715 drugs
2000 IU 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
75 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: Dextrose, Natural Cherry flavor, Stearic Acid, Magnesium Stearate, Citric Acid, Silicon Dioxide. These complete the product’s ingredient list but are not active constituents.

Interaction report

Vitamin D3 & K2 by aSquared Nutrition Drug Interactions

Want to check YOUR meds against Vitamin D3 & K2?

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
715Drugs
2 Major 80 Moderate 633 Minor

Ingredients driving the most interactions

Vitamin D3 715
Vitamin K2 2

Individual Drug Interactions

The ingredients in Vitamin D3 & K2 interact with 715 drugs. Click any drug to see the details.

2 of the 2 ingredients in Vitamin D3 & K2 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 D3 & K2 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 · 715 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 D3 & K2, from the product label.

aSquared Nutrition

See all aSquared Nutrition products
Name
aSquared Brands LLC
Street Address
40 Mildred Drive
City
Cheektowaga
State
NY
ZipCode
14225
Phone Number
1-716-218-3666
Pharmacist Counseling Corner

Vitamin D3 & K2 by aSquared Nutrition: Common Questions

Does Vitamin D3 & K2 by aSquared Nutrition interact with any medications?
Yes. Based on its ingredients, Vitamin D3 & K2 has a known interaction with 715 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 D3 & K2 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.
Can I take this if I'm on warfarin?
No—vitamin K2 can directly counteract warfarin's blood-thinning effect and is a major interaction. Do not take this product if you're on warfarin without explicit approval from your doctor or pharmacist.
Will this help my bones?
Vitamin D3 is proven effective for bone diseases like rickets and osteomalacia. Vitamin K2 shows some promise for osteoporosis, though the evidence is not as strong. Together they may support bone health, but your doctor is the best person to say whether this is right for you.
Is this safe to take during pregnancy?
Vitamin D3 is likely safe at recommended doses during pregnancy and breastfeeding, but use only under your doctor's guidance. Vitamin K2 is considered likely safe during both pregnancy and breastfeeding at normal dietary amounts; ask your provider before taking it as a supplement.
What are the side effects?
At recommended doses, both vitamins are well tolerated. Vitamin K2 can cause mild stomach upset, nausea, or diarrhea in some people. Vitamin D3 can cause toxicity if you take very high doses over time, with symptoms of high blood calcium levels.
Does this interact with my heart or cholesterol medications?
Yes—high-dose vitamin D3 can interact with heart rhythm drugs (verapamil, diltiazem), digoxin, and the cholesterol drug atorvastatin, as well as thiazide water pills. The main risk is that vitamin D can raise your blood calcium too high. Check with your doctor before taking this if you're on any of these.

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 D3 & K2 label
Go deeper

The Full Monographs Behind Vitamin D3 & K2’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 715 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 D3 & K2'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 26 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
  26. Kinesya E, Santoso D, Gde Arya N, et al. Vitamin D as adjuvant therapy for diabetic foot ulcers: Systematic review and meta-analysis approach. Clin Nutr ESPEN 2023;54:137-143. PubMed

See these in context on the Vitamin D monograph →

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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