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Dietary supplement

K-2 500 mcg MK-4 Ingredients & Drug Interactions

by Superior Source

K-2 500 mcg MK-4 label
See full label image
Tablet Or Pill Category: Botanical With Nutrients
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 K-2 500 mcg MK-4 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

K-2 500 mcg MK-4 is a dietary supplement by Superior Source with 2 active ingredients. Its ingredients are commonly taken for sugar substitute / sweetener, blood sugar support in diabetes, weight management.Based on those ingredients, 261 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Stevia leaf extract, 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 K-2 500 mcg MK-4 by Superior Source

Ask about any prescription or over-the-counter medication and we check it for interactions with K-2 500 mcg MK-4 by Superior Source — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of K-2 500 mcg MK-4 by Superior Source

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 Aug 13, 2026

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 2 of its 2 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

This product contains 2 active ingredients: vitamin K (as MK-4) at 500 mcg per dose, and stevia leaf extract as a sweetener. Vitamin K is an essential nutrient that helps your body produce clotting factors and supports bone health.

Stevia is a plant-derived sweetener with no calories. The tablet also contains inactive ingredients (lactose and acacia) used as fillers and binders.

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: supporting normal blood clotting and bone health.
  • We looked for evidence on: Hemorrhagic disease, Hypoprothrombinemia, Vitamin K-dependent clotting factors deficiency (VKCFD), Warfarin anticoagulation, Osteoporosis, Cardiovascular disease (CVD) — and 3 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, Warfarin anticoagulation, Vitamin K-dependent clotting factors deficiency (VKCFD).
  • Also on file: Vitamin K is rated "Possibly Effective" for Osteoporosis.

Vitamin K is effective for treating vitamin K-dependent clotting disorders, replacing clotting factors, reversing excessive warfarin anticoagulation, and treating certain types of bleeding. It is possibly effective for osteoporosis prevention or management.

Stevia leaf extract has insufficient evidence to reliably rate its effectiveness for diabetes, high blood pressure, or weight management—the small studies available show mixed results.

The evidence, ingredient by ingredient Stevia 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 K taken by mouth is generally well tolerated in food amounts and most supplements for healthy people; mild gastrointestinal side effects like nausea, stomach upset, and diarrhea can occur but are usually temporary. Purified stevia in food amounts is generally recognized as safe, but whole-leaf or high-dose supplement forms lack solid safety data, so caution is advised.

Minor side effects from stevia—such as headache, dizziness, nausea, bloating, and muscle pain—tend to resolve within the first week. Serious allergic reactions are rare.

Side effects, ingredient by ingredient Stevia 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 — Stevia, Vitamin K.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; diabetes medications; lithium.
  • For scale: 261 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before taking this product, double-check with your doctor or pharmacist if you take warfarin (Coumadin) or other blood thinners—vitamin K can reverse their effect. Also check if you take lithium (a mood stabilizer), blood pressure medications, or diabetes drugs, since stevia may theoretically raise lithium levels or increase the risk of low blood pressure or low blood sugar.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with clinical evidence supporting its stated purpose. Major medication interactions have been identified, and safety information is well characterized.

This product is most useful if you need vitamin K supplementation for clotting support or bone health and don't take warfarin. If you're on warfarin, lithium, blood pressure medication, or diabetes medication, check with your doctor or pharmacist before taking it—vitamin K especially can interfere with warfarin's effectiveness.

Even if you take other medications, run your exact drug list through the interaction checker on this page to be sure.

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

Assessment coverage: 2 of 2 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Dec 29, 2014.

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 K-2 500 mcg MK-4, straight from the product label.

Brand Superior Source
Net contents 60 MicroLingual(R) Instant Dissolve Tablet(s)
Market status On market
Date entered into DSLD Dec 29, 2014
DSLD ID 40476
Product type Botanical With Nutrients
Supplement form Tablet Or Pill
Dietary claims / uses All Other
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 K-2 500 mcg MK-4 by Superior Source, 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 MicroLingual(R) Tablet(s)
Maximum serving Sizes:
1 MicroLingual(R) Tablet(s)
Servings per container
60
IngredientAmount% DV
Stevia leaf extract1 mg--
Vitamin K500 mcg625%

Other ingredients: Lactose, Acacia

Tap any ingredient to jump to its full detail below.

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

Directions: As a dietary supplement, dissolve one MicroLingual(R) tablet under the tongue as directed by your healthcare provider. This product may also be chewed/swallowed.

Seals/Symbols

MicroLingual(R)

GMO FREE

FDA Statement of Identity

DIETARY SUPPLEMENT

General

ITEM # 90410 30603W P01 R04

Precautions

Warnings: If you are currently taking any anti-coagulant drugs (warfarin, coumadin, heparin, i.e.) or if you are pregnant/lactating, consult your healthcare provider before taking this product.

Keep out of reach of children.

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

See for yourself

K-2 500 mcg MK-4 by Superior Source label

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

K-2 500 mcg MK-4 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 K-2 500 mcg MK-4 by Superior Source

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

Serving size1 MicroLingual(R) Tablet(s) Dosage formTablet Or Pill 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.

Stevia leaf extract

Interacts with
259 drugs
1 mg per serving

Stevia is a plant-based, calorie-free sweetener that is widely used as a sugar alternative and is considered safe in normal food amounts by major regu...

Stevia leaf extract monograph & interactions

Vitamin K

Interacts with
2 drugs
500 mcg per serving Form: Menaquinone-4

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

Other (inactive) ingredients: Lactose, Acacia. These complete the product’s ingredient list but are not active constituents.

Interaction report

K-2 500 mcg MK-4 by Superior Source Drug Interactions

Want to check YOUR meds against K-2 500 mcg MK-4?

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
261Drugs
2 Major 1 Moderate 258 Minor

Ingredients driving the most interactions

Stevia leaf extract 259
Vitamin K 2

Individual Drug Interactions

The ingredients in K-2 500 mcg MK-4 interact with 261 drugs. Click any drug to see the details.

2 of the 2 ingredients in K-2 500 mcg MK-4 interact with drugs. Each result below shows which ingredient is responsible. Stevia leaf extract Vitamin K

Each ingredient & the kinds of drugs it affects

For each ingredient in K-2 500 mcg MK-4 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.

Stevia leaf extract3 drug types · 259 drugs

Lithium

Theoretically, stevia might decrease clearance and increase levels of lithium.
Animal research suggests that stevia extracts might have diuretic activity. Theoretically, increased reabsorption of lithium along with sodium might reduce excretion and increase levels of lithium.

Likelihood Possible Evidence D
Antidiabetes Drugs

Theoretically, stevia might increase the risk for hypoglycemia when combined with antidiabetes drugs.
Preliminary clinical research in patients with type 2 diabetes suggests that taking a single dose of stevia extract 1000 mg reduces postprandial blood glucose levels when taken with a meal. However, other clinical research in patients with type 1 or type 2 diabetes suggests that taking stevioside 250 mg three times daily does not significantly affect blood glucose levels or glycated hemoglobin (HbA1C) after three months of treatment.

Likelihood Possible Evidence D
Antihypertensive Drugs

Theoretically, combining stevia or stevia constituents with antihypertensive agents might increase the risk of hypotension.
Stevia extract and stevioside might lower blood pressure in patients with hypertension. However, other clinical research suggests that stevioside does not significantly lower blood pressure in patients with hypertension.

Likelihood Possible Evidence D
Stevia leaf extract 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 K-2 500 mcg MK-4, from the product label.

Superior Source

See all Superior Source products
Name
Superior Source
City
Los Angeles
State
CA
Phone Number
(800) 421-6175
Web Address
www.superiorsourcevitamins.com
Pharmacist Counseling Corner

K-2 500 mcg MK-4 by Superior Source: Common Questions

Does K-2 500 mcg MK-4 by Superior Source interact with any medications?
Yes. Based on its ingredients, K-2 500 mcg MK-4 has a known interaction with 261 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?
K-2 500 mcg MK-4 contains 2 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Can I take this if I'm on warfarin?
No—not without talking to your doctor first. Vitamin K directly counteracts warfarin's blood-thinning effect, so taking this product could reduce how well warfarin protects you. Your doctor may need to adjust your dose or monitor you more closely.
What are the side effects of stevia in this product?
The most common are headache, dizziness, nausea, bloating, and muscle pain. These are usually mild and tend to go away within the first week. Serious allergic reactions are rare.
Is vitamin K safe to take every day?
Vitamin K is generally well tolerated when taken daily in food amounts and most supplement doses for healthy people. The main caution is if you take warfarin or other blood thinners—consistency matters because changes in vitamin K intake can affect how these drugs work.
Does this product have any fillers?
Yes, it contains lactose and acacia as inactive ingredients to help form and bind the tablet.
Can I take this while pregnant?
Vitamin K is likely safe in pregnancy. However, we don't have safety data on file for stevia in pregnancy, so there isn't enough information to know either way. Talk with your doctor or pharmacist about whether this combination is right for you.

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.

K-2 500 mcg MK-4 label
Go deeper

The Full Monographs Behind K-2 500 mcg MK-4’s Ingredients

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

Herb & supplement monograph

Stevia

Interacts with 259 drugs

Stevia is a plant-based, calorie-free sweetener that is widely used as a sugar alternative and is considered safe in normal food amounts by major regulators. Purified stevia extracts have a...

Read the full Stevia 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

K-2 500 mcg MK-4'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 21 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.

Stevia 10 references
  1. Chan P, Xu DY, Liu JC, et al. The effect of stevioside on blood pressure and plasma catecholamines in spontaneously hypertensive rats. Life Sci 1998;63:1679-84. PubMed
  2. Melis MS. A crude extract of Stevia rebaudiana increases the renal plasma flow of normal and hypertensive rats. Braz J Med Biol Res 1996;29:669-75.
  3. Melis MS. Chronic administration of aqueous extract of Stevia rebaudiana in rats: renal effects. J Ethnopharmacol 1995;47:129-34. PubMed
  4. Melis MS, Sainati AR. Effect of calcium and verapamil on renal function of rats during treatment with stevioside. J Ethnopharmacol 1991;33:257-622. PubMed
  5. Hsieh MH, Chan P, Sue YM, et al. Efficacy and tolerability of oral stevioside in patients with mild essential hypertension: a two-year, randomized, placebo-controlled study. Clin Ther 2003;25:2797-808. PubMed
  6. Chan P, Tomlinson B, Chen YJ, et al. A double-blind placebo-controlled study of the effectiveness and tolerability of oral stevioside in human hypertension. Br J Clin Pharmacol 2000;50:215-20. PubMed
  7. Gregersen S, Jeppesen PB, Holst JJ, Hermansen K. Antihyperglycemic effects of stevioside in type 2 diabetic subjects. Metabolism 2004;53:73-6. PubMed
  8. Barriocanal LA, Palacios M, Benitez G, et al. Apparent lack of pharmacological effect of steviol glycosides used as sweeteners in humans. A pilot study of repeated exposures in some normotensive and hypotensive individuals and in Type 1 and Type 2 diabeti
  9. Ferri LA, Alves-Do-Prado W, Yamada SS, et al. Investigation of the antihypertensive effect of oral crude stevioside in patients with mild essential hypertension. Phytother Res 2006;20:732-6. PubMed
  10. Almiron-Roig E, Navas-Carretero S, Castelnuovo G, et al. Impact of acute consumption of beverages containing plant-based or alternative sweetener blends on postprandial appetite, food intake, metabolism, and gastro-intestinal symptoms: Results of the SWEE

See these in context on the Stevia monograph →

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

See these in context on the Vitamin K monograph →

Parts of this content are provided by the Therapeutic Research Center, LLC.

DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

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