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

Super K with Advanced K2 Complex Ingredients & Drug Interactions

by Life Extension

Super K with Advanced K2 Complex label
See full label image
Softgel 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 Super K with Advanced K2 Complex 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

Super K with Advanced K2 Complex is a dietary supplement by Life Extension with 2 active ingredients. Its ingredients are commonly taken for supporting normal blood clotting, bone health, heart and vascular health.Based on those ingredients, 207 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Vitamin C, Vitamin K. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Super K with Advanced K2 Complex by Life Extension

Ask about any prescription or over-the-counter medication and we check it for interactions with Super K with Advanced K2 Complex by Life Extension — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Super K with Advanced K2 Complex by Life Extension

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 (2,600 mcg) without saying how much of each component you get.

This product contains 4 active ingredients: Vitamin K (listed as a blend of component vitamins), Vitamin C, Vitamin K1, and Vitamin K2. The K vitamins support your blood's clotting ability and bone health, while Vitamin C acts as an antioxidant and supports immune function.

The inactive ingredients — olive oil, gelatin, glycerin, beeswax, purified water, and carob color — are fillers and capsule materials.

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: Bone health and cardiovascular support.
  • We looked for evidence on: Osteoporosis, Cardiovascular disease (CVD), Atherosclerosis, Hypercholesterolemia, Hypertension, Fractures — and 3 related terms.
  • The strongest evidence on file: Vitamin K is rated "Possibly Effective" for Osteoporosis (Natural Medicines).
  • Also on file: Vitamin C is rated "Possibly Effective" for Hypercholesterolemia, Hypertension.
  • Also on file: Vitamin C is rated "Possibly Ineffective" for Atherosclerosis, Cardiovascular disease (CVD), Fractures.

Vitamin K is Effective for correcting clotting factor deficiencies and managing warfarin-related anticoagulation, and Possibly Effective for osteoporosis. Vitamin C is Effective for vitamin C deficiency, and Possibly Effective for anemia of chronic disease, atrial fibrillation, cataracts, and exercise-induced respiratory infections.

The evidence, ingredient by ingredient Vitamin K Vitamin C

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 C and both forms of Vitamin K in this product are generally well tolerated at normal supplement doses. Vitamin C at very high doses can cause stomach upset, diarrhea, heartburn, nausea, and kidney stones (especially in people prone to them); these effects are more likely above 2 grams daily.

Vitamin K may cause mild stomach upset, nausea, diarrhea, or abdominal pain at normal doses. Serious adverse effects are rare with oral use.

During pregnancy and lactation, normal dietary amounts and standard prenatal vitamins containing these vitamins are considered safe. The data shows Vitamin K is Likely Safe during pregnancy and lactation.

For Vitamin C, normal amounts are considered safe, but avoid high-dose supplements during pregnancy unless your doctor advises it — one safety rating notes Possibly Unsafe for high doses. Talk with your doctor or pharmacist before starting any supplement during pregnancy or while breastfeeding.

Side effects, ingredient by ingredient Vitamin K Vitamin C

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 K, Vitamin C.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; cancer treatments.
  • For scale: 207 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 if you take warfarin (Coumadin) or any blood thinner — Vitamin K can reduce its effect (Major). Also double-check if you're on estrogen-based birth control or hormone replacement therapy, chemotherapy drugs, HIV medications like indinavir, thyroid medication (levothyroxine), antipsychotics like fluphenazine, or high-dose aluminum supplements.

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 a straightforward K and C vitamin blend — good for someone looking to support bone and clotting health. But if you take warfarin or any hormone therapy, estrogen-based birth control, chemotherapy, thyroid medication, or HIV drugs, you need to clear it with your pharmacist first.

Ask 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 Oct 25, 2018.

This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed

At a glance

General information

Key facts about Super K with Advanced K2 Complex, straight from the product label.

Brand Life Extension
Barcode (UPC) 737870203490
Net contents 90 Softgel(s)
Market status On market
Date entered into DSLD Oct 25, 2018
DSLD ID 182362
Product type Vitamin
Supplement form Softgel Capsule
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 Super K with Advanced K2 Complex by Life Extension, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
1 Softgel(s)
Maximum serving Sizes:
1 Softgel(s)
UPC/BARCODE
737870203490
IngredientAmount% DV
Vitamin K2600 mcg3250%
Vitamin C10 mg17%
Vitamin K21000 mcg--
Vitamin K11500 mcg--
Vitamin K2100 mcg--

Other ingredients: extra virgin Olive Oil, Gelatin, Glycerin, Beeswax, purified Water, Carob color

Tap any ingredient to jump to its full detail below.

Label statements
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
General Statements

Scan for product info

Promotes Arterial Health and Healthy Bones

General

Q02034B

Suggested/Recommended/Usage/Directions

Read the entire label and follow the directions carefully prior to use. Directions: Take one (1) softgel daily with food, or as recommended by a healthcare practitioner.

1 Daily

Precautions

Caution: If you are taking anticoagulant or antiplatelet medications, or have a bleeding disorder, consult with your healthcare provider before taking this product.

Warnings: Keep out of reach of children.

Do not exceed recommended dose. Do not purchase if outer seal is broken or damaged.

When using nutritional supplements, please consult with your physician if you are undergoing treatment for a medical condition or if you are pregnant or lactating.

Contains soybeans.

To report a serious adverse event or obtain product information, contact 1-866-280-2852.

Formulation

Non-GMO

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

Super K with Advanced K2 Complex

Contains soybeans.

FDA Statement of Identity

Dietary Supplement

Storage

Store tightly closed in a cool, dry place.

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

See for yourself

Super K with Advanced K2 Complex by Life Extension label

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

Super K with Advanced K2 Complex 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 Super K with Advanced K2 Complex by Life Extension

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

Serving size1 Softgel(s) Dosage formSoftgel Capsule 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
2600 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 C

Interacts with
207 drugs
10 mg per serving Form: Ascorbyl Palmitate

Vitamin C (ascorbic acid) is an essential nutrient your body needs but cannot make, so you must get it from food or supplements. It's important for im...

Vitamin C monograph & interactions

Other (inactive) ingredients: Extra virgin Olive Oil, Gelatin, Glycerin, Beeswax, Purified Water, Carob color. These complete the product’s ingredient list but are not active constituents.

Interaction report

Super K with Advanced K2 Complex by Life Extension Drug Interactions

Want to check YOUR meds against Super K with Advanced K2 Complex?

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
207Drugs
2 Major 99 Moderate 106 Minor

Ingredients driving the most interactions

Vitamin C 207
Vitamin K 2

Individual Drug Interactions

The ingredients in Super K with Advanced K2 Complex interact with 207 drugs. Click any drug to see the details.

2 of the 2 ingredients in Super K with Advanced K2 Complex interact with drugs. Each result below shows which ingredient is responsible. Vitamin C Vitamin K

Each ingredient & the kinds of drugs it affects

For each ingredient in Super K with Advanced K2 Complex 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 C13 drug types · 207 drugs

Alkylating Agents

Theoretically, antioxidant effects of vitamin C might reduce the effectiveness of alkylating agents.
The use of antioxidants like vitamin C during chemotherapy is controversial. There is concern that antioxidants could reduce the activity of chemotherapy drugs that generate free radicals, such as cyclophosphamide, chlorambucil, carmustine, busulfan, and thiotepa. In contrast, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that could interfere with apoptosis (cell death) of cancer cells. More evidence is needed to determine what effect, if any, antioxidants such as vitamin C have on chemotherapy.

Likelihood Possible Evidence D
Aluminum

Vitamin C can increase the amount of aluminum absorbed from aluminum compounds.
Research in animals and humans shows that vitamin C increases aluminum absorption, theoretically by chelating aluminum and keeping it in solution where it is available for absorption. In people with normal renal function, urinary excretion of aluminum will likely increase, making aluminum retention and toxicity unlikely. Patients with renal failure who take aluminum-containing compounds such as phosphate binders should avoid vitamin C supplements in doses above the recommended dietary allowances.

Likelihood Probable Evidence B
Antitumor Antibiotics

Theoretically, the antioxidant effects of vitamin C might reduce the effectiveness of antitumor antibiotics.
The use of antioxidants like vitamin C during chemotherapy is controversial. There is concern that antioxidants could reduce the activity of chemotherapy drugs which generate free radicals, such as doxorubicin. In contrast, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that could interfere with apoptosis (cell death) of cancer cells. More evidence is needed to determine what effects, if any, antioxidants such as vitamin C have on chemotherapy.

Likelihood Possible Evidence D
Estrogens

Vitamin C might increase blood levels of estrogens.
Increases in plasma estrogen levels of up to 55% occur under some circumstances when vitamin C is taken concurrently with oral contraceptives or hormone replacement therapy, including topical products. It is suggested that vitamin C prevents oxidation of estrogen in the tissues, regenerates oxidized estrogen, and reduces sulfate conjugation of estrogen in the gut wall. When tissue levels of vitamin C are high, these processes are already maximized and supplemental vitamin C does not have any effect on estrogen levels. Increases in plasma estrogen levels may occur when patients who are deficient in vitamin C take supplements. Monitor these patients for estrogen-related side effects.

Likelihood Probable Evidence B
Fluphenazine (Prolixin)

Theoretically, vitamin C might decrease levels of fluphenazine.
In one patient there was a clinically significant decrease in fluphenazine levels when vitamin C (500 mg twice daily) was started. The mechanism is not known, and there is no further data to confirm this interaction.

Likelihood Possible Evidence D
Indinavir (Crixivan)

Vitamin C can modestly reduce indinavir levels.
One pharmacokinetic study shows that taking vitamin C 1 gram orally once daily along with indinavir 800 mg orally three times daily reduces the area under the concentration-time curve of indinavir by 14%. The mechanism of this interaction is unknown, but it is unlikely to be clinically significant in most patients. The effect of higher doses of vitamin C on indinavir levels is unknown.

Likelihood Probable Evidence B
Levothyroxine (Synthroid, Others)

Vitamin C can increase levothyroxine absorption.
Two clinical studies in adults with poorly controlled hypothyroidism show that swallowing levothyroxine with a glass of water containing vitamin C 500-1000 mg in solution reduces thyroid stimulating hormone (TSH) levels and increases thyroxine (T4) levels when compared with taking levothyroxine alone. This suggests that vitamin C increases the oral absorption of levothyroxine, possibly due to a reduction in pH.

Likelihood Probable Evidence B
Warfarin (Coumadin)

High-dose vitamin C might reduce the levels and effectiveness of warfarin.
Vitamin C in high doses may cause diarrhea and possibly reduce warfarin absorption. There are reports of two people who took up to 16 grams daily of vitamin C and had a reduction in prothrombin time. Lower doses of 5-10 grams daily can also reduce warfarin absorption. In many cases, this does not seem to be clinically significant. However, a case of warfarin resistance has been reported for a patient who took vitamin C 500 mg twice daily. Cessation of vitamin C supplementation resulted in a rapid increase in international normalized ratio (INR). Tell patients taking warfarin to avoid taking vitamin C in excessively high doses (greater than 10 grams daily). Lower doses may be safe, but the anticoagulation activity of warfarin should be monitored. Patients who are stabilized on warfarin while taking vitamin C should avoid adjusting vitamin C dosage to prevent the possibility of warfarin resistance.

Likelihood Possible Evidence D
Acetaminophen (Tylenol, Others)

High-dose vitamin C might slightly prolong the clearance of acetaminophen.
A small pharmacokinetic study in healthy volunteers shows that taking high-dose vitamin C (3 grams) 1.5 hours after taking acetaminophen 1 gram slightly increases the apparent half-life of acetaminophen from around 2.3 hours to 3.1 hours. Ascorbic acid competitively inhibits sulfate conjugation of acetaminophen. However, to compensate, elimination of acetaminophen glucuronide and unconjugated acetaminophen increases. This effect is not likely to be clinically significant.

Likelihood Probable Evidence B
Aspirin

Acidification of the urine by vitamin C might increase aspirin levels.
It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels. However, short-term use of up to 6 grams daily of vitamin C does not seem to affect urinary pH or salicylate excretion, suggesting this interaction is not clinically significant.

Likelihood Possible Evidence B
Choline Magnesium Trisalicylate (Trilisate)

Acidification of the urine by vitamin C might increase choline magnesium trisalicylate levels.
It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels. However, short-term use of up to 6 grams daily of vitamin C does not seem to affect urinary pH or salicylate excretion, suggesting this interaction probably is not clinically significant.

Likelihood Possible Evidence B
Niacin

Vitamin C might decrease the beneficial effects of niacin on high-density lipoprotein (HDL) cholesterol levels.
A combination of niacin and simvastatin (Zocor) effectively raises HDL cholesterol levels in patients with coronary disease and low HDL levels. Clinical research shows that taking a combination of antioxidants (vitamin C, vitamin E, beta-carotene, and selenium) along with niacin and simvastatin (Zocor) attenuates this rise in HDL, specifically the HDL-2 and apolipoprotein A1 fractions, by more than 50% in patients with coronary disease. It is not known whether this adverse effect is due to a single antioxidant such as vitamin C, or to the combination. It also is not known whether it will occur in other patient populations.

Likelihood Possible Evidence A
Salsalate (Disalcid)

Acidification of the urine by vitamin C might increase salsalate levels.
It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels. However, short-term use of up to 6 grams/day vitamin C does not seem to affect urinary pH or salicylate excretion, suggesting this interaction probably is not clinically significant.

Likelihood Possible Evidence B
Vitamin C 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 Super K with Advanced K2 Complex, from the product label.

Life Extension

See all Life Extension products
Name
Quality Supplements and Vitamins, Inc.
City
Ft. Lauderdale
State
FL
ZipCode
33309
Phone Number
1-866-280-2852
Web Address
LifeExtension.com
Pharmacist Counseling Corner

Super K with Advanced K2 Complex by Life Extension: Common Questions

Does Super K with Advanced K2 Complex by Life Extension interact with any medications?
Yes. Based on its ingredients, Super K with Advanced K2 Complex has a known interaction with 207 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?
Super K with Advanced K2 Complex 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.
I'm on birth control pills. Can I take this?
The Vitamin C in this product might increase your estrogen levels. This is a Moderate interaction, so check with your pharmacist before starting. They can tell you whether it affects your specific birth control or if you need any adjustments.
What does the Vitamin K do?
Vitamin K supports your blood's ability to clot and helps maintain bone health. This product contains both K1 and K2 forms, which work on clotting factors and bone strength.
Will this give me kidney stones?
Vitamin C at very high doses can increase kidney stone risk, especially in people with a history of them. This product contains Vitamin C at normal supplement levels, but if you're prone to kidney stones or have kidney problems, mention it to your pharmacist.
Is it safe during pregnancy?
Normal dietary amounts of these vitamins are considered safe in pregnancy. Vitamin K is Likely Safe. For Vitamin C, avoid high-dose supplements unless your doctor recommends them — the data shows mixed safety for high doses in pregnancy. Talk with your doctor before starting any supplement while pregnant.
What side effects should I expect?
Most people tolerate this product well. You might notice mild stomach upset, nausea, diarrhea, or heartburn — these are more common with Vitamin C at higher doses. Stop and call your pharmacist if you have any unusual reactions.
Can I take this with my thyroid medication?
Vitamin C can increase how much levothyroxine your body absorbs (Moderate interaction), which might change your thyroid levels. Your doctor may need to adjust your dose. Check with your pharmacist before adding this product.

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.

Super K with Advanced K2 Complex label
Go deeper

The Full Monographs Behind Super K with Advanced K2 Complex’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 C

Interacts with 207 drugs

Vitamin C (ascorbic acid) is an essential nutrient your body needs but cannot make, so you must get it from food or supplements. It's important for immune function, collagen, and acts as an...

Read the full Vitamin C monograph →
Sources

Sources & How We Checked

Super K with Advanced K2 Complex'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 62 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 C 51 references
  1. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
  2. Back DJ, Breckenridge AM, MacIver M, et al. Interaction of ethinyloestradiol with ascorbic acid in man. Br Med J (Clin Res Ed) 1981;282:1516.
  3. Morris JC, Beeley L, Ballantine N. Interaction of ethinyloestradiol with ascorbic acid in man [letter]. Br Med J (Clin Res Ed) 1981;283:503.
  4. Labriola D, Livingston R. Possible interactions between dietary antioxidants and chemotherapy. Oncology 1999;13:1003-8.
  5. Dwyer JH, Merz NB, Shirocre AM, et al. Progression of early atherosclerosis and intake of vitamin C and vitamin E from supplements and food. The Los Angeles Atherosclerosis Study. 41st Annual Conference on Cardiovascular Disease Epidemiology and Prevent
  6. Levine M, Rumsey SC, Daruwala R, et al. Criteria and recommendations for vitamin C intake. JAMA 1999;281:1415-23. PubMed
  7. Hansten PD, Horn JR. Drug Interactions Analysis and Management. Vancouver, WA: Applied Therapeutics Inc., 1997 and updates.
  8. Segal S, Kaminski S. Drug-nutrient interactions. American Druggist 1996 Jul;42-8.
  9. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Vitamin C, Vitamin E, Selenium, and Carotenoids. Washington, DC: National Academy Press, 2000. Available at: http://www.nap.edu/books/0309069351/html/.
  10. Houston JB, Levy G. Drug biotransformation interactions in man VI: Acetaminophen and ascorbic acid. J Pharm Sci 1976;65:1218-21. PubMed
  11. Brown BG, Zhao XQ, Chait A, et al. Simvastatin and niacin, antioxidant vitamins, or the combination for the prevention of coronary disease. N Engl J Med 2001;345:1583-93. DOI
  12. Rosenthal G. Interaction of ascorbic acid and warfarin. JAMA 1971;215:1671. DOI
  13. Hume R, Johnstone JM, Weyers E. Interaction of ascorbic acid and warfarin. JAMA 1972;219:1479. DOI
  14. Smith EC, Skalski RJ, Johnson GC, Rossi GV. Interaction of ascorbic acid and warfarin. JAMA 1972;221:1166. DOI
  15. Traxer O, Huet B, Poindexter J, et al. Effect of ascorbic acid consumption on urinary stone risk factors. J Urol 2003;170:397-401.. PubMed
  16. Domingo JL, Gomez M, Llobet JM, Richart C. Effect of ascorbic acid on gastrointestinal aluminum absorption (letter). Lancet 1991;338:1467.
  17. Domingo JL, Gomez M, Llobet JM, Corbella J. Influence of some dietary constituents on aluminum absorption and retention in rats. Kidney Int 1991;39:598-601. PubMed
  18. Partridge NA, Regnier FE, White JL, Hem SL. Influence of dietary constituents on intestinal absorption of aluminum. Kidney Int 1989;35:1413-7. PubMed
  19. Mc Leod DC, Nahata MC. Inefficacy of ascorbic acid as a urinary acidifier (letter). N Engl J Med 1977;296:1413. DOI
  20. Hansten PD, Hayton WL. Effect of antacid and ascorbic acid on serum salicylate concentration. J Clin Pharmacol 1980;20:326-31. PubMed
  21. Dysken MW, Cumming RJ, Channon RA, Davis JM. Drug interaction between ascorbic acid and fluphenazine. JAMA 1979;241:2008. DOI
  22. Vihtamaki T, Parantainen J, Koivisto AM, et al. Oral ascorbic acid increases plasma oestradiol during postmenopausal hormone replacement therapy. Maturitas 2002;42:129-35. PubMed
  23. Slain D, Amsden JR, Khakoo RA, et al. Effect of high-dose vitamin C on the steady-state pharmacokinetics of the protease inhibitor indinavir in healthy volunteers. Pharmacotherapy 2005;25:165-70. PubMed
  24. Cheung MC, Zhao XQ, Chait A, et al. Antioxidant supplements block the response of HDL to simvastatin-niacin therapy in patients with coronary artery disease and low HDL. Arterioscler Thromb Vasc Biol 2001;21:1320-6. PubMed
  25. Feetam CL, Leach RH, Meynell MJ. Lack of a clinically important interaction between warfarin and ascorbic acid. Toxicol Appl Pharmacol 1975;31:544-7. PubMed
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See these in context on the Vitamin C monograph →

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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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