Major interaction on record — check this product against your medications before combining. Check your meds →
Dietary supplement

A-D-K Essential Vitamins Ingredients & Drug Interactions

by Terra Origin

A-D-K Essential Vitamins label
See full label image
Capsule Category: Vitamin
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking A-D-K Essential Vitamins 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

A-D-K Essential Vitamins is a dietary supplement by Terra Origin with 3 active ingredients. Its ingredients are commonly taken for supporting normal blood clotting, bone health, heart and vascular health.Based on those ingredients, 945 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Vitamin D, Vitamin A, Vitamin K. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against A-D-K Essential Vitamins by Terra Origin

Ask about any prescription or over-the-counter medication and we check it for interactions with A-D-K Essential Vitamins by Terra Origin — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of A-D-K Essential Vitamins by Terra Origin

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 Jul 11, 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.
  • “Vitamin K” is listed as a grouped ingredient — the label gives one combined amount (1,000 mcg) without saying how much of each component you get.

A-D-K Essential Vitamins contains four active ingredients: Vitamin K1, Vitamin K2, Vitamin A, and Vitamin D. Vitamins K1 and K2 are different forms of vitamin K, which your body needs to make clotting factors and build bone.

Vitamin A supports your eyes, skin, and immune system. Vitamin D helps you absorb calcium and maintain bone health.

The capsules also contain several inactive ingredients—medium-chain triglycerides oil, olive oil, hypromellose (a capsule coating), and silicon dioxide (an anti-caking agent).

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 heart and immune health.
  • We looked for evidence on: Cardiovascular disease (CVD), Fall prevention, Fractures, Corticosteroid-induced osteoporosis, Hyperparathyroidism-related bone loss, Hemorrhagic disease — and 4 related terms.
  • The strongest evidence on file: Vitamin K is rated "Effective" for Hemorrhagic disease (Natural Medicines).
  • Also on file: Vitamin K is rated "Effective" for Hypoprothrombinemia.
  • Also on file: Vitamin D is rated "Likely Effective" for Corticosteroid-induced osteoporosis.

Vitamin K (both K1 and K2) is effective for treating vitamin K deficiency, vitamin K-dependent clotting factor deficiency, and hemorrhagic disease, and it's also effective for reversing the effects of warfarin when needed. It's possibly effective for osteoporosis.

Vitamin A is effective for vitamin A deficiency and is possibly effective for oral leukoplakia, aging skin, measles, ulcerative colitis, and bronchopulmonary dysplasia. Vitamin D is effective for familial hypophosphatemia, osteomalacia, renal bone disease, rickets, and hypoparathyroidism.

The evidence for bone health benefits (osteoporosis prevention with K; bone support with D) suggests these vitamins play important roles, but the strength of evidence varies by condition.

The evidence, ingredient by ingredient Vitamin K Vitamin A Vitamin D

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 3 of the 3 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 3 of 3.
  • General safety write-ups exist for 3 of 3.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Vitamin K is generally well tolerated when taken by mouth. The most common side effects are mild—diarrhea, nausea, and stomach upset.

Vitamin A is also generally well tolerated at recommended doses, but high doses can accumulate in your body and become toxic, causing headache, liver damage, and serious skin symptoms. Vitamin D is well tolerated at recommended doses, but excessive amounts over time can lead to vitamin D toxicity with high calcium levels in your blood.

The safety data for vitamin A in pregnancy is mixed—normal dietary amounts are fine, but high-dose supplements (especially retinol) should be avoided because they may cause birth defects. Vitamin K and D are considered likely safe in pregnancy at recommended amounts.

No pregnancy or breastfeeding data is on file for vitamin D in our system, so talk with your doctor or pharmacist about your individual situation.

Side effects, ingredient by ingredient Vitamin K Vitamin A Vitamin D

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?
  • 3 of the 3 matched ingredients can interact with medications — Vitamin D, Vitamin A, 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: 946 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 with your pharmacist before taking this product if you're on: warfarin or other blood thinners (Major risk from vitamin K); retinoids, hepatotoxic drugs, tetracycline antibiotics, or high-dose vitamin A supplements (Moderate risks from vitamin A); thiazide diuretics, verapamil, diltiazem, digoxin, atorvastatin, calcipotriene, or other CYP3A4 substrates (Moderate to Minor risks from vitamin D). No interactions are documented for the inactive ingredients we could check.

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.

If you're taking warfarin or any blood thinner, do not take this product without checking with your pharmacist first—vitamin K will interfere. If you're on retinoids, high-dose vitamin A supplements, tetracycline antibiotics, heart rhythm medications, or digoxin, this needs a careful review too.

Otherwise, for general vitamin support in healthy people not on interacting medications, it's a straightforward multivitamin. Run your exact medications through the checker below before you start.

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

Assessment coverage: 4 of 4 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Apr 22, 2021.

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 A-D-K Essential Vitamins, straight from the product label.

Brand Terra Origin
Barcode (UPC) 857668007588
Net contents 60 Liquid Capsule(s)
Market status On market
Date entered into DSLD Apr 22, 2021
DSLD ID 247853
Product type Vitamin
Supplement form Capsule
Dietary claims / uses Nutrient, All Other, Structure/Function
Intended target group(s) Vegan, Vegetarian, 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 A-D-K Essential Vitamins by Terra Origin, 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 Liquid Capsule(s)
Maximum serving Sizes:
1 Liquid Capsule(s)
Servings per container
60
UPC/BARCODE
857668007588
IngredientAmount% DV
Vitamin K1000 mcg833%
Vitamin K1500 mcg--
Vitamin A1500 mcg167%
Vitamin D125 mcg625%
Vitamin K2500 mcg--

Other ingredients: Medium Chain Triglycerides Oil, Olive Oil, Hypromellose, 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.
Formula

For bone, heart & immune health Specially formulated using high-quality nutraceuticals. Terra Origin A-D-K Essential Vitamins are a vegan, non-GMO daily supplement that strengthens and supports your bones, heart, and immune system. This high-potency blend of Vitamins A, D and K are packed in a MCT Oil liquid capsule to help generate cell production, absorb calcium from the bloodstream into the bone, strengthen bone density and provide cardiovascular support.

Fat-soluble vitamins with MCT Oil for maximum absorption

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

Benefits Supports bone structure, density & integrity Increases calcium absorption Promotes a strong immune system Provides cardiovascular support

Non GMO Gluten free

Vegan

High-potency liquid capsules Bone & immune health Calcium absorption Cardiovascular support

Made in the U.S.A. from ingredients grown in the U.S.A. and other countries.

FDA Statement of Identity

Dietary Supplement

Brand IP Statement(s)

2020 Terra Origin, Inc.

Suggested/Recommended/Usage/Directions

Suggested Use Adults take 1 capsule daily with 8 ounces of water or your favorite beverage. For optimal results, take with food.

Storage

Warnings Store in a cool, dry place.

Precautions

Use only as directed.

If you are pregnant, nursing or taking medication, consult your doctor before taking.

Keep out of reach of children.

Do not use this product if the safety seal is broken or missing.

General Statements

For more information please visit terraorigin.com

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

See for yourself

A-D-K Essential Vitamins by Terra Origin label

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

A-D-K Essential Vitamins 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 A-D-K Essential Vitamins by Terra Origin

These are the 3 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 Liquid Capsule(s) Dosage formCapsule Servings per container60 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 K

Interacts with
2 drugs
1000 mcg per serving

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

Vitamin K monograph & interactions

Vitamin A

Interacts with
387 drugs
1500 mcg per serving Form: Retinyl Palmitate

Vitamin A is an essential nutrient important for vision, skin, immune function, and growth. Most people get enough from a balanced diet, and supplemen...

Vitamin A monograph & interactions

Vitamin D

Interacts with
715 drugs
125 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

Other (inactive) ingredients: Medium Chain Triglycerides Oil, Olive Oil, Hypromellose, Silicon Dioxide. These complete the product’s ingredient list but are not active constituents.

Interaction report

A-D-K Essential Vitamins by Terra Origin Drug Interactions

Want to check YOUR meds against A-D-K Essential Vitamins?

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
945Drugs
11 Major 448 Moderate 486 Minor

Ingredients driving the most interactions

Vitamin D 715
Vitamin A 387
Vitamin K 2

Individual Drug Interactions

The ingredients in A-D-K Essential Vitamins interact with 945 drugs. Click any drug to see the details.

3 of the 3 ingredients in A-D-K Essential Vitamins interact with drugs. Each result below shows which ingredient is responsible. Vitamin D Vitamin A Vitamin K

Each ingredient & the kinds of drugs it affects

For each ingredient in A-D-K Essential Vitamins 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

Vitamin A4 drug types · 387 drugs

Retinoids

Concomitant use of retinoids with vitamin A supplements might produce supratherapeutic vitamin A levels.
Retinoids, which are vitamin A derivatives, could have additive toxic effects when taken with vitamin A supplements.

Likelihood Probable Evidence D
Hepatotoxic Drugs

Theoretically, taking high doses of vitamin A in combination with other potentially hepatotoxic drugs might increase the risk of liver disease.
The tolerable upper intake level (UL) is the highest level of intake that is likely to pose no risk of adverse effects. Doses of vitamin A above the UL can cause hepatotoxicity, ranging from elevated liver enzymes to liver failure.

Likelihood Possible Evidence C
Tetracycline Antibiotics

Theoretically, taking tetracycline antibiotics with high doses of vitamin A can increase the risk of pseudotumor cerebri.
Benign intracranial hypertension (pseudotumor cerebri) can occur with tetracyclines and with acute or chronic vitamin A toxicity. Case reports suggest that taking tetracyclines and vitamin A concurrently can increase the risk of this condition. Avoid high doses of vitamin A in people taking tetracyclines chronically.

Likelihood Possible Evidence D
Warfarin (Coumadin)

Theoretically, high doses of vitamin A could increase the risk of bleeding with warfarin.
Vitamin A toxicity is associated with hemorrhage and hypoprothrombinemia, possibly due to vitamin K antagonism. Advise patients taking warfarin to avoid doses of vitamin A above the tolerable upper intake level of 10,000 IU/day for adults.

Likelihood Possible Evidence D
Vitamin A full monograph & interactions

Vitamin K1 drug type · 2 drugs

Warfarin (Coumadin)

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

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

Brand information

Manufacturer and brand details for A-D-K Essential Vitamins, from the product label.

Terra Origin

See all Terra Origin products
Name
Terra Origin Inc
Street Address
330 Oser Avenue
City
Hauppauge
State
NY
ZipCode
11788
Phone Number
(631)300-2306
Web Address
www.TerraOrigin.com
Pharmacist Counseling Corner

A-D-K Essential Vitamins by Terra Origin: Common Questions

Does A-D-K Essential Vitamins by Terra Origin interact with any medications?
Yes. Based on its ingredients, A-D-K Essential Vitamins has a known interaction with 945 medications, including 11 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
A-D-K Essential Vitamins contains 3 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?
Not without talking to your doctor or pharmacist first. Both vitamin K1 and K2 in this product directly reduce warfarin's blood-thinning effect, which could be dangerous. Your provider may need to adjust your warfarin dose or choose a different vitamin product.
What are the most common side effects?
Vitamin K taken by mouth most often causes mild stomach upset—nausea, diarrhea, or abdominal discomfort. Vitamin A at high doses can cause headache and skin changes. Vitamin D toxicity from excessive doses can cause high blood calcium levels. At recommended doses, these vitamins are generally well tolerated.
Is this safe to take during pregnancy?
Vitamin K and the dose of vitamin A in a multivitamin are generally considered safe during pregnancy, but high-dose vitamin A supplements should be avoided because they may cause birth defects. Vitamin D has no pregnancy safety data on file with us. Talk with your doctor about whether this product is right for you during pregnancy.
Can this affect my cholesterol or heart medications?
Yes, potentially. Vitamin D may reduce how well atorvastatin (Lipitor) is absorbed. Vitamin D can also raise blood calcium to unsafe levels if you're taking verapamil, diltiazem, or digoxin for heart rhythm problems. Check your specific medications with us before starting.
What is vitamin K2, and is it different from K1?
Vitamin K2 is a different form of vitamin K than K1. Both are needed for blood clotting and bone health, but they come from different sources and your body handles them slightly differently. Both forms interact with warfarin in the same way, so the caution is the same.

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.

A-D-K Essential Vitamins label
Go deeper

The Full Monographs Behind A-D-K Essential Vitamins’s Ingredients

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

Herb & supplement monograph

Vitamin K

Interacts with 2 drugs

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

Read the full Vitamin K monograph → Herb & supplement monograph

Vitamin A

Interacts with 387 drugs

Vitamin A is an essential nutrient important for vision, skin, immune function, and growth. Most people get enough from a balanced diet, and supplements are mainly useful for correcting a tr...

Read the full Vitamin A monograph → 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 →
Sources

Sources & How We Checked

A-D-K Essential Vitamins'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 68 references behind this product’s interaction data

Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.

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

See these in context on the Vitamin K monograph →

Vitamin A 31 references
  1. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
  2. Griffiths JK. The vitamin A paradox. J Pediatr 2000;137:604-7.. PubMed
  3. Hardman JG, Limbird LL, Molinoff PB, eds. Goodman and Gillman's The Pharmacological Basis of Therapeutics, 9th ed. New York, NY: McGraw-Hill, 1996.
  4. Hansten PD, Horn JR. Drug Interactions Analysis and Management. Vancouver, WA: Applied Therapeutics Inc., 1997 and updates.
  5. FDA Talk Paper. Vitamin A and birth defects (T95-56). Food and Drug Administration, U.S. Department of Health and Human Services, Rockville, MD. October 6, 1995.
  6. Russell RM. The vitamin A spectrum: from deficiency to toxicity. Am J Clin Nutr 2000;71:878-84. PubMed
  7. 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.
  8. Feskanich D, Singh V, Willett WC, Colditz GA. Vitamin A intake and hip fractures among postmenopausal women. JAMA 2002;287:47-54. PubMed
  9. Melhus H, Michaelsson K, Kindmark A, et al. Excessive dietary intake of vitamin A is associated with reduced bone mineral density and increased risk for hip fracture. Ann Intern Med 1998;129:770-8. PubMed
  10. Michaelsson K, Lithell H, Vessby B, Melhus H. Serum retinol levels and the risk of fracture. N Engl J Med 2003;348:287-94.. PubMed
  11. Botterweck AA, van den Brandt PA, Goldbohm RA. Vitamins, carotenoids, dietary fiber, and the risk of gastric carcinoma: results from a prospective study after 6.3 years of follow-up. Cancer 2000;88:737-48.. DOI
  12. Meyskens FL Jr, Graham V, Chvapil M, et al. A phase I trial of beta-all-trans-retinoic acid delivered via a collagen sponge and a cervical cap for mild or moderate intraepithelial cervical neoplasia. J Natl Cancer Inst 1983;71:921-5..
  13. Hathcock JN, Hattan DG, Jenkins MY, et al. Evaluation of vitamin A toxicity. Am J Clin Nutr 1990;52:183-202.. PubMed
  14. Walters BN, Gubbay SS. Tetracycline and benign intracranial hypertension: report of five cases. Br Med J 1981;282:19-20.. PubMed
  15. Pearson MG, Littlewood SM, Bowden AN. Tetracycline and benign intracranial hypertension (letter). Br Med J 1981;282:568-9.. PubMed
  16. Azais-Braesco V, Pascal G. Vitamin A in pregnancy: requirements and safety limits. Am J Clin Nutr 2000;71:1325S-33S. PubMed
  17. Smedts HP, de Vries JH, Rakhshandehroo M, et al. High maternal vitamin E intake by diet or supplements is associated with congenital heart defects in the offspring. BJOG 2009;116:416-23. PubMed
  18. Grotto, I., Mimouni, M., Gdalevich, M., and Mimouni, D. Vitamin A supplementation and childhood morbidity from diarrhea and respiratory infections: a meta-analysis. J Pediatr 2003;142(3):297-304. PubMed
  19. Mahalanabis, D., Lahiri, M., Paul, D., Gupta, S., Gupta, A., Wahed, M. A., and Khaled, M. A. Randomized, double-blind, placebo-controlled clinical trial of the efficacy of treatment with zinc or vitamin A in infants and young children with severe acute l
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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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