Major interaction on record — check this product against your medications before combining. Based on 2 of 4 ingredients. Check your meds →
Dietary supplement

Omega Defense Ingredients & Drug Interactions

by Whitaker Nutrition

Omega Defense label
See full label image
Softgel Capsule Category: Other Combinations
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 Omega Defense 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

Omega Defense is a dietary supplement by Whitaker Nutrition with 4 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 D, MenaQ7. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Omega Defense by Whitaker Nutrition

Ask about any prescription or over-the-counter medication and we check it for interactions with Omega Defense by Whitaker Nutrition — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
Prefer a human? Send your question to our licensed pharmacists — free, answered by email within 24 hours.

HelloPharmacist Scorecard of Omega Defense by Whitaker 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 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 4 of its 4 active ingredients.
  • “Calamarine Oil concentrate” is listed as a grouped ingredient — the label gives one combined amount (2 Gram(s)) without saying how much of each component you get.

Omega Defense has four active ingredients: vitamin D, docosahexaenoic acid ethyl ester (a long-chain omega-3), eicosapentaenoic acid ethyl ester (another omega-3), and MenaQ7 (a form of vitamin K derived from calamarine oil concentrate). The product also contains inactive ingredients including gelatin, glycerin, and several flavoring and stabilizing agents.

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: advanced cardiovascular health.
  • We looked for evidence on: Cardiovascular disease (CVD), Atrial fibrillation, Heart failure, Hyperlipidemia, Metabolic syndrome, vascular health — and 2 related terms.
  • The strongest evidence on file: Vitamin D is rated "Possibly Effective" for Heart failure (Natural Medicines).
  • Also on file: Vitamin D is rated "Possibly Ineffective" for Cardiovascular disease (CVD).
  • Also on file: Vitamin D is rated "Insufficient Reliable Evidence To Rate" for Atrial fibrillation, Hyperlipidemia, Metabolic syndrome.

Vitamin D in this product is effective for treating familial hypophosphatemia, osteomalacia (soft bones from vitamin D deficiency), renal osteodystrophy (bone disease from kidney problems), rickets, and hypoparathyroidism. Vitamin K (MenaQ7) is effective for hypoprothrombinemia (low blood clotting factors) and vitamin K-dependent clotting factor deficiency, and shows possibly effective evidence for osteoporosis.

The effectiveness of the omega-3 ingredients in this product isn't covered in our data.

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 D is generally well tolerated at recommended doses but can cause toxicity if taken in very high amounts over time — symptoms include high blood calcium levels, anemia, and bone loss. It's often used in pregnancy and lactation under medical guidance.

Vitamin K (MenaQ7) is generally safe at dietary amounts; oral vitamin K causes mild gastrointestinal side effects like nausea, stomach upset, and diarrhea in some people. Both ingredients warrant a conversation with your doctor before taking higher amounts than you'd get from food.

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.

Check before starting if you take warfarin or any blood thinner — vitamin K directly reduces its effect. Also double-check if you're on a heart medication (verapamil, diltiazem, digoxin), a thiazide diuretic for blood pressure, atorvastatin (Lipitor) for cholesterol, or any drug processed by the CYP3A4 pathway in your liver.

Talk it over with your doctor or pharmacist.

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.

This product is worth considering if you're deficient in vitamin D or K and your doctor recommends supplementation. But if you take warfarin, any heart rhythm medication, blood pressure drugs, cholesterol medication, or any other prescription, check with your own pharmacist or doctor before starting — the interactions here are real and could affect how your drugs work.

Your healthcare provider can tell you whether Omega Defense is right for your situation.

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

Assessment coverage: 2 of 4 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Aug 22, 2024.

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 Omega Defense, straight from the product label.

Brand Whitaker Nutrition
Barcode (UPC) 810047390398
Net contents 60 Softgel(s)
Market status On market
Date entered into DSLD Aug 22, 2024
DSLD ID 315950
Product type Other Combinations
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 Omega Defense by Whitaker 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:
2 Softgel(s)
Maximum serving Sizes:
2 Softgel(s)
Servings per container
30
UPC/BARCODE
810047390398
IngredientAmount% DV
Calories20 Calorie(s)--
Vitamin D50 mcg250%
Cholesterol15 mg5%
Total Fat2 Gram(s)3%
Docosahexaenoic Acid Ethyl Ester800 mg--
Eicosapentaenoic Acid Ethyl Ester200 mg--
Calamarine Oil concentrate2 Gram(s)--
MenaQ750 mcg--

Other ingredients: Gelatin, Glycerin, Water, Purified, Carob extract, Medium Chain Triglyceride, Lemon Oil, Caramel, Mixed Tocopherols

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.
Formulation

Unconditionally guaranteed for purity and labeled potency.

For advanced cardiovascular health

GF Gluten Free

Storage

Store bottle with cap tightly closed in a cool, dry place.

Precautions

Precautions: Consult a health care practitioner if you take warfarin or other blood thinners, or are pregnant or nursing, have a serious medical condition, or use any medications.

Keep out of reach of children.

Brand IP Statement(s)

CalaMarine is a registered trademark of Pharma Marine AS. MenaQ7 Vitamin K2 as MK-7 MenaQ7 is a registered trademark of NattoPharma ASA, Norway; Patented in the United States and Canada. US Patent Numbers 8,728, 553 and 8,354,129; Canada Patent Number 2,347,387.

Seals/Symbols

Friend of the Sea

FDA Disclaimer Statement

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

Formula

Omega Defense includes CalaMarine, MenaQ7 MK-7, and Vitamin D3

FDA Statement of Identity

Dietary Supplement

Suggested/Recommended/Usage/Directions

Doctor's suggested use: Take 2 softgels once daily.

General Statements

Almost out? Call 1-800-722-8008 or visit healthydirections.com Choose refill & save and never run out!

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

See for yourself

Omega Defense by Whitaker Nutrition label

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

Omega Defense 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 Omega Defense by Whitaker Nutrition

These are the 4 active ingredients this product is made of. Select any to open its full monograph.

Serving size2 Softgel(s) Dosage formSoftgel Capsule Servings per container30 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 D

Interacts with
715 drugs
50 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 D monograph & interactions

Calamarine Oil concentrate

2 Gram(s) per serving Form: from Squid
  • › Docosahexaenoic Acid Ethyl Ester
  • › Eicosapentaenoic Acid Ethyl Ester

MenaQ7

Interacts with
2 drugs
50 mcg per serving Form: Menaquinone-7, Vitamin K2

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...

MenaQ7 monograph & interactions

Other (inactive) ingredients: Gelatin, Glycerin, Water, Purified, Carob extract, Medium Chain Triglyceride, Lemon Oil, Caramel, Mixed Tocopherols. These complete the product’s ingredient list but are not active constituents.

Interaction report

Omega Defense by Whitaker Nutrition Drug Interactions

Want to check YOUR meds against Omega Defense?

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 D 715
MenaQ7 2

Individual Drug Interactions

The ingredients in Omega Defense interact with 715 drugs. Click any drug to see the details.

2 of the 4 ingredients in Omega Defense interact with drugs. Each result below shows which ingredient is responsible. Vitamin D MenaQ7

Each ingredient & the kinds of drugs it affects

For each ingredient in Omega Defense 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 D8 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 D full monograph & interactions

MenaQ71 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
MenaQ7 full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Omega Defense, from the product label.

Whitaker Nutrition

See all Whitaker Nutrition products
Name
Healthy Directions
City
Bethesda
State
MD
ZipCode
20817
Phone Number
1-800-722-8008
Web Address
healthydirections.com
Pharmacist Counseling Corner

Omega Defense by Whitaker Nutrition: Common Questions

Does Omega Defense by Whitaker Nutrition interact with any medications?
Yes. Based on its ingredients, Omega Defense 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?
Omega Defense contains 4 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 while I'm pregnant?
Vitamin D is rated likely safe in pregnancy and is often used under medical supervision. Vitamin K (MenaQ7) is also rated likely safe in pregnancy and lactation. But there's a second rating for vitamin D marked possibly unsafe — it depends on the dose and your individual situation. Talk with your doctor before starting to make sure it's right for you.
What are the side effects?
Vitamin D is well tolerated orally at normal doses. Very high doses over time can cause toxicity, with symptoms like high blood calcium, bone loss, and anemia. Vitamin K can cause mild stomach upset, nausea, abdominal pain, and diarrhea in some people.
Is this product gluten-free?
That information isn't in our product data. Check the product label or contact the manufacturer directly.
How much vitamin D is in each softgel?
We don't have the specific dose per capsule listed in our data — check the product label or packaging for that amount.
Is this effective for bone health?
Vitamin D is effective for rickets and other bone diseases caused by vitamin D deficiency, and vitamin K is possibly effective for osteoporosis. For bone health specifically, talk with your doctor about whether these doses are appropriate for your needs.

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

Not sure if Omega Defense is safe with your meds?

Our pharmacists answer your medication & supplement questions — free.

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.

Omega Defense label
Go deeper

The Full Monographs Behind Omega Defense’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

Omega Defense'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

Keep exploring
Supplement interaction checker › Check any supplement or product against your medications Drug–drug interactions › Check two or more of your medications against each other Browse medications A–Z › Every drug we've checked against herbs & supplements NDC & pricing lookup › Find a drug’s NDCs, packaging and costs Ask a pharmacist › Free, personal answer from our licensed team