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

K2D3 Ingredients & Drug Interactions

by youtheory

K2D3 label
See full label image
Liquid Category: Multi-vitamin And Mineral (mvm)
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 9, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking K2D3 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

K2D3 is a dietary supplement by youtheory with 4 active ingredients. Its ingredients are commonly taken for replacing fluids and electrolytes, preventing dehydration during exercise or illness, treating low blood sodium (under medical care).Based on those ingredients, 883 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Vitamin D3, Sodium, Calcium. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against K2D3 by youtheory

Ask about any prescription or over-the-counter medication and we check it for interactions with K2D3 by youtheory — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of K2D3 by youtheory

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 4 of its 4 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

youtheory K2D3 is a liquid supplement with 4 active ingredients: sodium, calcium, vitamin D3, and K2Vital (a form of vitamin K). Sodium is an electrolyte your body needs to regulate fluid balance and blood pressure, though excess amounts are linked to high blood pressure and heart strain.

Calcium supports bone health, muscle function, and nerve transmission. Vitamin D3 (cholecalciferol) helps your body absorb calcium and regulate immune function.

K2Vital is a bioavailable form of vitamin K, which plays a role in bone mineralization and blood clotting. The product also contains inactive ingredients including water, xylitol, cane sugar, natural flavors, calcium citrate, sodium chloride, malic acid, vitamin E acetate, xanthan gum, stevia leaf extract, and citric acid.

These are excipients that give the liquid its taste, texture, and stability.

Does it work?

Strong evidence
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed
Strong

Clinical evidence supports at least one of this product's ingredients for its stated purpose.

Why this rating?
  • The label markets this product for: bone health, cardiovascular function and brain energy.
  • We looked for evidence on: Cardiovascular disease (CVD), Cognitive function, Fractures, Corticosteroid-induced osteoporosis, Fall prevention, Frailty — and 3 related terms.
  • The strongest evidence on file: Calcium is rated "Likely Effective" for Osteoporosis (Natural Medicines).
  • Also on file: Calcium is rated "Likely Effective" for Corticosteroid-induced osteoporosis.
  • Also on file: Vitamin D is rated "Likely Effective" for Corticosteroid-induced osteoporosis.

The evidence for these ingredients varies by intended use. Calcium is effective for bone loss (osteoporosis), low blood calcium (hypocalcemia), high potassium (hyperkalemia), and indigestion.

Vitamin D3 is effective for familial hypophosphatemia, rickets, osteomalacia (soft bones), renal bone disease, and hypoparathyroidism. Vitamin K is effective for blood-clotting disorders and hypoprothrombinemia (low clotting factors), and is possibly effective for osteoporosis.

For sodium, evidence is limited to cystic fibrosis (likely effective) and amphotericin B kidney damage (possibly effective); its role in other conditions lacks reliable evidence in our data.

The evidence, ingredient by ingredient Sodium Calcium 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 4 of the 4 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 4 of 4.
  • General safety write-ups exist for 4 of 4.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Calcium is generally well tolerated at recommended amounts; the most common side effects are mild gastrointestinal—belching, constipation, or stomach upset. Very high doses carry rare risks including kidney stones and calciphylaxis.

Vitamin D3 is well tolerated at standard doses, though excessive doses over time can cause vitamin D toxicity with symptoms tied to high blood calcium. Vitamin K is generally well tolerated; the most common side effects are nausea, abdominal pain, and diarrhea.

Sodium is well tolerated at normal dietary amounts, but too much is linked to high blood pressure and heart strain, and people should avoid sodium supplements or very high intake without medical advice. For pregnancy and breastfeeding: calcium is likely safe during pregnancy and lactation at recommended amounts.

Vitamin D3 is likely safe during pregnancy and lactation at recommended doses but possibly unsafe in excessive amounts. Vitamin K is likely safe during pregnancy and lactation.

Sodium shows mixed data—likely safe but also possibly unsafe depending on circumstances—so talk with your doctor or pharmacist for personalized guidance. There is insufficient data on file for K2Vital in pregnancy and breastfeeding; check with your healthcare provider before use.

Side effects, ingredient by ingredient Sodium Calcium 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?
  • 4 of the 4 matched ingredients can interact with medications — Calcium, Vitamin D, Vitamin K, Sodium.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; heart-rhythm medications; lithium.
  • For scale: 884 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 youtheory K2D3, check with your doctor or pharmacist if you take warfarin or other blood thinners (Major interaction with vitamin K). Also confirm you're clear on calcium's Major interactions with dolutegravir, elvitegravir, or intravenous ceftriaxone.

If you take lithium, blood pressure medications, thyroid hormone, heart rhythm drugs like sotalol or digoxin, corticosteroids, or atorvastatin, the Moderate interactions are significant enough to discuss beforehand.

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.

youtheory K2D3 may be right for you if you're looking to support bone health and have no blood-clotting medications or conditions that restrict sodium or calcium intake. If you take warfarin or any other blood thinner, have kidney disease, high blood pressure, heart disease, or take thyroid medication, HIV antiretrovirals, digoxin, or certain other drugs, talk with your doctor or pharmacist before starting—the interactions can be serious.

Check your exact medications against the search tool on this page, and then discuss the results with your own healthcare provider.

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 Feb 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 K2D3, straight from the product label.

Brand youtheory
Barcode (UPC) 850021920302
Net contents 12 Fluid Ounce(s); 360 Milliliter(s)
Market status On market
Date entered into DSLD Feb 22, 2024
DSLD ID 305893
Product type Multi-vitamin And Mineral (mvm)
Supplement form Liquid
Dietary claims / uses Nutrient, All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Women (not pregnant or lactating), Gluten Free, Dairy 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 K2D3 by youtheory, 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:
30 mL
Maximum serving Sizes:
30 mL
Servings per container
12
UPC/BARCODE
850021920302
IngredientAmount% DV
Calories15 Calorie(s)--
Total Carbohydrates3 Gram(s)1%
Sodium60 mg3%
Calcium32 mg2%
Vitamin D3125 mcg625%
Added Sugars1 Gram(s)2%
Total Sugars1 Gram(s)--
K2Vital100 mcg83%

Other ingredients: Water, Purified, Xylitol, Cane Sugar, Natural Flavors, Calcium Citrate, Sodium Chloride, Malic Acid, D-Alpha-Tocopherol Acetate, Xanthan Gum, Stevia Leaf Extract, Citric Acid

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

Essential daily vitamins

Peach flavor

Youtheory K2D3 provides essential nutrients that enable the body to properly use calcium for a variety of functions in normal metabolism. K2 + D3 also complement one another in the promotion of bone growth and cardiovascular function.

Vitamin K has well-established roles in promoting normal bone mineralization and cardiovascular function. Vitamin D is responsible for ensuring absorption and retention of calcium.

Natural flavors

Formulation

Promotes brain health Helps support energy production

Promotes calcium absorption Helps support cardiovascular function Promotes bone health

Great tasting. Ready to drink. Promotes brain health

Dairy free Soy free No gluten ingredients

FDA Statement of Identity

Dietary Supplement

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.

General Statements

12 - 1 fl oz (30 mL)

Precautions

Usage warnings: Check with your doctor before using this product if you are taking medication or have any medical conditions. Do not exceed the recommended daily intake.

Do not use if you are pregnant or nursing.

Suggested/Recommended/Usage/Directions

Suggested Use: (Adults) Shake well and consume one (1) liquid packet per day directly by mouth.

Brand IP Statement(s)

K2Vital is a registered trademark of Kappa Bioscience.

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

See for yourself

K2D3 by youtheory label

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

K2D3 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 K2D3 by youtheory

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

Serving size30 mL Dosage formLiquid Servings per container12 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.

Sodium

Interacts with
205 drugs
60 mg per serving

Sodium is an essential mineral and electrolyte your body needs to balance fluids, support nerves, and help muscles work. Most people in modern diets g...

Sodium monograph & interactions

Calcium

Interacts with
168 drugs
32 mg per serving

Calcium is an essential mineral your body needs for strong bones, nerve signaling, and muscle function, and supplements can help fill gaps when diet f...

Calcium monograph & interactions

Vitamin D3

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 D3 monograph & interactions

K2Vital

Interacts with
2 drugs
100 mcg per serving Form: 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...

K2Vital monograph & interactions

Other (inactive) ingredients: Water, Purified, Xylitol, Cane Sugar, Natural Flavors, Calcium Citrate, Sodium Chloride, Malic Acid, D-Alpha-Tocopherol Acetate, Xanthan Gum, Stevia Leaf Extract, Citric Acid. These complete the product’s ingredient list but are not active constituents.

Interaction report

K2D3 by youtheory Drug Interactions

Want to check YOUR meds against K2D3?

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
883Drugs
9 Major 290 Moderate 584 Minor

Ingredients driving the most interactions

Vitamin D3 715
Sodium 205
Calcium 168
K2Vital 2

Individual Drug Interactions

The ingredients in K2D3 interact with 883 drugs. Click any drug to see the details.

4 of the 4 ingredients in K2D3 interact with drugs. Each result below shows which ingredient is responsible. Vitamin D3 Sodium Calcium K2Vital

Each ingredient & the kinds of drugs it affects

For each ingredient in K2D3 with known interactions, here are the types of medications they can affect. Open any type for the detail — or search your exact drug in the checker above.

Vitamin D38 drug types · 715 drugs

Aluminum

Vitamin D might increase aluminum absorption and toxicity, but this has only been reported in people with renal failure.
The protein that transports calcium across the intestinal wall can also bind and transport aluminum. This protein is stimulated by vitamin D, which may therefore increase aluminum absorption. This mechanism may contribute to increased aluminum levels and toxicity in people with renal failure, when they take vitamin D and aluminum-containing phosphate binders chronically.

Likelihood Probable Evidence B
Atorvastatin (Lipitor)

Vitamin D might reduce absorption of atorvastatin.
A small, low-quality clinical study shows that taking vitamin D reduces levels of atorvastatin and its active metabolites by up to 55%. However, while atorvastatin levels decreased, total cholesterol, low-density lipoprotein (LDL) cholesterol, and high-density lipoprotein (HDL) cholesterol levels did not substantially change. Atorvastatin is metabolized in the gut by CYP3A4 enzymes, and researchers theorized that vitamin D might induce CYP3A4, causing reduced levels of atorvastatin. However, this proposed mechanism was not specifically studied.

Likelihood Probable Evidence B
Calcipotriene (Dovonex)

Taking calcipotriene with vitamin D increases the risk for hypercalcemia.
Calcipotriene is a vitamin D analog used topically for psoriasis. It can be absorbed in sufficient amounts to cause systemic effects, including hypercalcemia. Theoretically, combining calcipotriene with vitamin D supplements might increase the risk of hypercalcemia.

Likelihood Probable Evidence D
Digoxin (Lanoxin)

Theoretically, hypercalcemia induced by high-dose vitamin D can increase the risk of arrhythmia from digoxin.
High doses of vitamin D can cause hypercalcemia. Hypercalcemia increases the risk of fatal cardiac arrhythmias with digoxin. Avoid vitamin D doses above the tolerable upper intake level (4000 IU daily for adults) and monitor serum calcium levels in people taking vitamin D and digoxin concurrently.

Likelihood Possible Evidence D
Diltiazem (Cardizem, Others)

Theoretically, hypercalcemia induced by high-dose vitamin D can reduce the therapeutic effects of diltiazem for arrhythmia.
High doses of vitamin D can cause hypercalcemia. Hypercalcemia can reduce the effectiveness of verapamil in atrial fibrillation. Theoretically this could also occur with diltiazem. Avoid vitamin D doses above the tolerable upper intake level (4000 IU daily for adults) and monitor serum calcium levels in people taking vitamin D and diltiazem concurrently.

Likelihood Probable Evidence B
Thiazide Diuretics

Theoretically, taking thiazide diuretics and high-dose vitamin D can increase the risk of hypercalcemia.
Thiazide diuretics decrease urinary calcium excretion, which could lead to hypercalcemia if vitamin D supplements are taken concurrently. This has been reported in people being treated with vitamin D for hypoparathyroidism, and also in elderly people with normal parathyroid function who were taking a thiazide, vitamin D, and calcium-containing antacids daily.

Likelihood Probable Evidence D
Verapamil (Calan, Others)

Hypercalcemia induced by high-dose vitamin D can reduce the therapeutic effects of verapamil for arrhythmia.
Hypercalcemia due to high doses of vitamin D can reduce the effectiveness of verapamil in atrial fibrillation. Avoid vitamin D doses above the tolerable upper intake level (4000 IU daily for adults) and monitor serum calcium levels in people taking vitamin D and verapamil concurrently.

Likelihood Probable Evidence B
Cytochrome P450 3A4 (Cyp3A4) Substrates

Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.
There is some concern that vitamin D might induce CYP3A4. In vitro research suggests that vitamin D induces CYP3A4 transcription. Additionally, observational research has found that increased UV light exposure and serum vitamin D levels are associated with decreased serum levels of CYP3A4 substrates such as tacrolimus and sirolimus, while no association between UV light exposure or vitamin D levels and levels of mycophenolic acid, a non-CYP3A4 substrate, was found. A small, low-quality clinical study shows that taking vitamin D reduces levels of the CYP3A4 substrate atorvastatin and its active metabolites by up to 55%; however, the clinical effects of atorvastatin were not reduced. While researchers theorized that vitamin D might induce CYP3A4, this proposed mechanism was not specifically studied.

Likelihood Possible Evidence D
Vitamin D3 full monograph & interactions

Sodium7 drug types · 205 drugs

Antihypertensive Drugs

Theoretically, a high intake of dietary sodium might reduce the effectiveness of antihypertensive drugs.
High intake of dietary sodium can increase systolic and diastolic blood pressure. Also, high intake of sodium may necessitate increased use of antihypertensive medications to achieve blood pressure control in some patients, such as those with chronic kidney disease.

Likelihood Probable Evidence A
Corticosteroids

Concomitant use of mineralocorticoids and some glucocorticoids with sodium supplements might increase the risk of hypernatremia.
Mineralocorticoids and some glucocorticoids (corticosteroids) cause sodium retention. This effect is dose-related and depends on mineralocorticoid potency. It is most common with hydrocortisone, cortisone, and fludrocortisone, followed by prednisone and prednisolone.

Likelihood Possible Evidence D
Didanosine (Videx)

Concomitant use of didanosine with additional sodium from dietary or supplemental sources may increase the risk of hypernatremia.
Didanosine formulations contain a significant amount of sodium.

Likelihood Probable Evidence C
Lithium

Altering dietary intake of sodium might alter the levels and clinical effects of lithium.
High sodium intake can reduce plasma concentrations of lithium by increasing lithium excretion. Reducing sodium intake can significantly increase plasma concentrations of lithium and cause lithium toxicity in patients being treated with lithium carbonate. Stabilizing sodium intake is shown to reduce the percentage of patients with lithium level fluctuations above 0.8 mEq/L. Patients taking lithium should avoid significant alterations in their dietary intake of sodium.

Likelihood Probable Evidence B
Sodium Phosphates

Theoretically, concomitant use of sodium phosphate with sodium supplements might increase the risk of hypernatremia.
Use of high doses (> 45 mL in 24 hours) of sodium phosphate, such as those used for bowel cleansing before surgery, can lead to serious electrolyte disturbances, including hypernatremia. The risk of hypernatremia is highest in the elderly and people with other risk factors for electrolyte disturbances.

Likelihood Possible Evidence D
Sodium-Containing Drugs

Concomitant use of sodium-containing drugs with additional sodium from dietary or supplemental sources may increase the risk of hypernatremia and long-term sodium-related complications.
The Chronic Disease Risk Reduction (CDRR) intake level of 2.3 grams of sodium daily indicates the intake at which it is believed that chronic disease risk increases for the apparently healthy population. Some medications contain high quantities of sodium. When used in conjunction with sodium supplements or high-sodium diets, the CDRR may be exceeded. Additionally, concomitant use may increase the risk for hypernatremia; this risk is highest in the elderly and people with other risk factors for electrolyte disturbances.

Likelihood Possible Evidence D
Tolvaptan (Samsca)

Theoretically, concomitant use of tolvaptan with sodium might increase the risk of hypernatremia.
Tolvaptan is a vasopressin receptor 2 antagonist that is used to increase sodium levels in patients with hyponatremia. Patients taking tolvaptan should use caution with the use of sodium salts such as sodium chloride.

Likelihood Probable Evidence C
Sodium full monograph & interactions

Calcium18 drug types · 168 drugs

Ceftriaxone (Rocephin)

Co-administration of intravenous calcium and ceftriaxone can result in precipitation of a ceftriaxone-calcium salt in the lungs and kidneys.
Avoid administering intravenous calcium in any form, such as parenteral nutrition or Lactated Ringers, within 48 hours of intravenous ceftriaxone. Case reports in neonates show that administering intravenous ceftriaxone and calcium can result in precipitation of a ceftriaxone-calcium salt in the lungs and kidneys. In several cases, neonates have died as a result of this interaction. So far there are no reports in adults; however, there is still concern that this interaction might occur in adults.

Likelihood Probable Evidence D
Dolutegravir (Tivicay)

Calcium seems to reduce levels of dolutegravir.
Advise patients to take dolutegravir either 2 hours before or 6 hours after taking calcium supplements. Pharmacokinetic research suggests that taking calcium carbonate 1200 mg concomitantly with dolutegravir 50 mg reduces plasma levels of dolutegravir by almost 40%. Calcium appears to decrease levels of dolutegravir through chelation.

Likelihood Probable Evidence B
Elvitegravir (Vitekta)

Calcium seems to reduce levels of elvitegravir.
Advise patients to take elvitegravir either 2 hours before or 2 hours after taking calcium supplements. Pharmacokinetic research suggests that taking calcium along with elvitegravir can reduce blood levels of elvitegravir through chelation.

Likelihood Probable Evidence B
Aluminum

Calcium citrate might increase aluminum absorption and toxicity. Other types of calcium do not increase aluminum absorption.
Calcium citrate can increase the absorption of aluminum when taken with aluminum hydroxide. The increase in aluminum levels may become toxic, particularly in individuals with kidney disease. However, the effect of calcium citrate on aluminum absorption is due to the citrate anion rather than calcium cation. Calcium acetate does not appear to increase aluminum absorption.

Likelihood Possible Evidence B
Bictegravir/Emtricitabine/Tenofovir Alafenamide (Biktarvy)

Calcium might decrease levels of bictegravir/emtricitabine/tenofovir alafenamide by reducing its absorption when taken in a fasting state.
Advise patients that bictegravir/emtricitabine/tenofovir alafenamide and calcium can be taken together if taken with food. However, if taken on an empty stomach, bictegravir/emtricitabine/tenofovir alafenamide should not be taken with, or 2 hours after, calcium containing products.

Likelihood Probable Evidence D
Bisphosphonates

Calcium reduces the absorption of bisphosphonates.
Advise patients to take bisphosphonates at least 30 minutes before calcium, but preferably at a different time of day. Calcium supplements decrease absorption of bisphosphonates.

Likelihood Probable Evidence C
Calcipotriene (Dovonex)

Taking calcipotriene with calcium might increase 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 calcium supplements might increase the risk of hypercalcemia.

Likelihood Possible Evidence B
Digoxin (Lanoxin)

Using intravenous calcium with digoxin might increase the risk of fatal cardiac arrhythmias.
Hypercalcemia increases the risk of fatal cardiac arrhythmias with digoxin. However, one retrospective analysis of clinical data suggests that intravenous calcium does not increase the risk of dysrhythmias or mortality in patients receiving digoxin.

Likelihood Possible Evidence B
Diltiazem (Cardizem, Others)

Theoretically, calcium may reduce the therapeutic effects of diltiazem.
Hypercalcemia can reduce the effectiveness of verapamil in atrial fibrillation. Theoretically, calcium might increase this risk of hypercalcemia and reduce the effectiveness of diltiazem.

Likelihood Probable Evidence D
Levothyroxine (Synthroid, Others)

Calcium seems to reduce the absorption and effectiveness of levothyroxine.
Advise patients to take levothyroxine and calcium supplements at least 4 hours apart. Calcium reduces levothyroxine absorption, probably by forming insoluble complexes. Calcium carbonate supplements reduce effectiveness of levothyroxine in patients with hypothyroidism.

Likelihood Probable Evidence B
Lithium

Theoretically, concomitant use of calcium and lithium may increase this risk of hypercalcemia.
Clinical research suggests that long-term use of lithium may cause hypercalcemia in 10% to 60% of patients. Theoretically, concomitant use of lithium and calcium supplements may further increase this risk.

Likelihood Possible Evidence B
Quinolone Antibiotics

Calcium seems to reduce the absorption of quinolone antibiotics.
Advise patients to take oral quinolones at least 2 hours before or 4-6 hours after calcium supplements or calcium-fortified foods. Taking calcium at the same time as oral quinolones can reduce quinolone absorption. Calcium binds to quinolones in the gut.

Likelihood Probable Evidence B
Raltegravir (Isentress)

Calcium may reduce levels of raltegravir.
Pharmacokinetic research shows that taking a single dose of calcium carbonate 3000 mg along with raltegravir 400 mg twice daily modestly decreases the mean area under the curve of raltegravir, but the decrease does not necessitate a dose adjustment of raltegravir. However, a case of elevated HIV-1 RNA levels and documented resistance to raltegravir has been reported for a patient taking calcium carbonate 1 gram three times daily plus vitamin D3 (cholecalciferol) 400 IU three times daily in combination with raltegravir 400 mg twice daily for 11 months. It is thought that calcium reduced raltegravir levels by chelation, leading to treatment failure.

Likelihood Possible Evidence B
Sotalol (Betapace)

Calcium seems to reduce the absorption of sotalol.
Advise patients to separate doses by at least 2 hours before or 4-6 hours after calcium. Calcium appears to reduce the absorption of sotalol, probably by forming insoluble complexes.

Likelihood Possible Evidence B
Tetracycline Antibiotics

Calcium seems to reduce the absorption of tetracycline antibiotics.
Advise patients to take oral tetracyclines at least 2 hours before, or 4-6 hours after calcium supplements. Taking calcium at the same time as oral tetracyclines can reduce tetracycline absorption. Calcium binds to tetracyclines in the gut.

Likelihood Probable Evidence C
Thiazide Diuretics

Taking calcium along with thiazides might increase the risk of hypercalcemia and renal failure.
Thiazides reduce calcium excretion by the kidneys. Using thiazides along with moderately large amounts of calcium carbonate increases the risk of milk-alkali syndrome (hypercalcemia, metabolic alkalosis, renal failure). Patients may need to have their serum calcium levels and/or parathyroid function monitored regularly.

Likelihood Probable Evidence C
Verapamil (Calan, Others)

Theoretically, calcium may reduce the therapeutic effects of verapamil.
Hypercalcemia can reduce the effectiveness of verapamil in atrial fibrillation. Theoretically, use of calcium supplements may increase this risk of hypercalcemia and reduce the effectiveness of verapamil.

Likelihood Probable Evidence D
Calcium Channel Blockers

Intravenous calcium may decrease the effects of calcium channel blockers; oral calcium is unlikely to have this effect.
Intravenous calcium is used to decrease the effects of calcium channel blockers in the management of overdose. Intravenous calcium gluconate has been used before intravenous verapamil (Isoptin) to prevent or reduce the hypotensive effects without affecting the antiarrhythmic effects. But there is no evidence that dietary or supplemental calcium when taken orally interacts with calcium channel blockers.

Likelihood Unlikely Evidence D
Calcium full monograph & interactions

K2Vital1 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
K2Vital full monograph & interactions
The maker

Brand information

Manufacturer and brand details for K2D3, from the product label.

youtheory

See all youtheory products
Name
Nutrawise
City
Irvine
State
CA
ZipCode
92618
Phone Number
888.271.8976
Web Address
youtheory.com
Pharmacist Counseling Corner

K2D3 by youtheory: Common Questions

Does K2D3 by youtheory interact with any medications?
Yes. Based on its ingredients, K2D3 has a known interaction with 883 medications, including 9 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
K2D3 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.
Will this interfere with my warfarin?
Yes—this is a serious concern. The K2Vital (vitamin K) in this product can reverse warfarin's blood-thinning effect. Do not take this supplement without talking to your doctor first. They may need to adjust your warfarin dose or monitor you more closely.
Can I take this if I'm on levothyroxine for my thyroid?
The calcium in this product can reduce how much levothyroxine your body absorbs, making it less effective. If you take levothyroxine, separate it from this supplement by at least 4 hours. Talk to your pharmacist or doctor about the best timing for you.
Is this safe during pregnancy?
Calcium, vitamin D3, and vitamin K are generally considered likely safe at recommended doses during pregnancy, but data on K2Vital is not on file. Sodium data shows mixed results. Talk with your doctor or midwife before starting any new supplement in pregnancy—they know your full picture.
What's the liquid form made of besides the four active ingredients?
The inactive ingredients are water, xylitol (a sugar alcohol), cane sugar, natural flavors, calcium citrate, sodium chloride, malic acid, vitamin E acetate, xanthan gum, stevia leaf extract, and citric acid. These are fillers and flavoring agents that don't add therapeutic benefit.
Does vitamin D3 in this product affect my cholesterol medicine?
Possibly. A small study shows vitamin D may lower atorvastatin levels by up to 55%, though cholesterol numbers didn't always change in that study. If you take atorvastatin, mention this product to your doctor or pharmacist.
Can I take this with my blood pressure pills?
The sodium in this supplement may reduce how well blood pressure medications work, and high sodium can raise your blood pressure directly. If you take blood pressure drugs, talk to your doctor before starting—they may want to monitor your blood pressure more closely or adjust your dose.

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

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Go deeper

The Full Monographs Behind K2D3’s Ingredients

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

Herb & supplement monograph

Sodium

Interacts with 205 drugs

Sodium is an essential mineral and electrolyte your body needs to balance fluids, support nerves, and help muscles work. Most people in modern diets get more than enough—often too much—from...

Read the full Sodium monograph → Herb & supplement monograph

Calcium

Interacts with 168 drugs

Calcium is an essential mineral your body needs for strong bones, nerve signaling, and muscle function, and supplements can help fill gaps when diet falls short. Most people do best getting...

Read the full Calcium 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 → 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

K2D3'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 137 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.

Sodium 38 references
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  2. Food and Drug Administration Science Background: Safety of Sodium Phosphates Oral Solution. September 17, 2001. Available at: http://www.fda.gov/cder/drug/safety/sodiumphospate.htm
  3. Coton T, Mallaret C, Coilliot C, Carre D, Guisset M. Severe acute ulcerated gastritis induced by salt. Presse Med 2009;38(3):499-500. PubMed
  4. Frings-Meuthen P, Buehlmeier J, Baecker N, et al. High sodium chloride intake exacerbates immobilization-induced bone resorption and protein losses. J Appl Physiol 2011;111(2):537-542. PubMed
  5. Frings-Meuthen P, Baecker N, Heer M. Low-grade metabolic acidosis may be the cause of sodium chloride-induced exaggerated bone resorption. J Bone Miner Res 2008;23(4):517-524. PubMed
  6. Alam S, Johnson AG. A meta-analysis of randomised controlled trials (RCT) among healthy normotensive and essential hypertensive elderly patients to determine the effect of high salt (NaCl) diet of blood pressure. J Hum Hypertens 1999;13(6):367-74.
  7. Boudville N, Ward S, Benaroia M, House AA. Increased sodium intake correlates with greater use of antihypertensive agents by subjects with chronic kidney disease. Am J Hypertens 2005;18(10):1300-5. PubMed
  8. Bennett WM. Drug interactions and consequences of sodium restriction. Am J Clin Nutr 1997;65(2 Suppl):678S-681S. PubMed
  9. Okusa MD, Crystal LJ. Clinical manifestations and management of acute lithium intoxication. Am J Med 1994;97(4):383-9. PubMed
  10. Food and Nutrition Board, Institute of Medicine. Dietary reference intakes for water, potassium, sodium, chloride, and sulfate. Washington, DC: National Academy Press, 2005. Available at: http://www.nap.edu/openbook.php?record_id=10925. DOI
  11. D'Elia L, Rossi G, Ippolito R, Cappuccio FP, Strazzullo P. Habitual salt intake and risk of gastric cancer: a meta-analysis of prospective studies. Clin Nutr 2012;31(4):489-98. PubMed
  12. Goldsmith SR. Hyponatremia in heart failure: time for a trial. J Card Fail 2013;19(6):398-400. PubMed
  13. Willocks L, Brettle R, Keen J, Valentine C, Pinching AJ. Formulations of didanosine (ddI) and salt overload. Lancet 1992;339(8786):190.
  14. Chen L, Zhang Z, Chen W, Whelton PK, Appel LJ. Lower Sodium Intake and Risk of Headaches: Results From the Trial of Nonpharmacologic Interventions in the Elderly. Am J Public Health. 2016;106(7):1270-5. PubMed
  15. Cook NR, Appel LJ, Whelton PK. Lower levels of sodium intake and reduced cardiovascular risk. Circulation. 2014;129(9):981-9. PubMed
  16. Cook NR, Appel LJ, Whelton PK. Sodium Intake and All-Cause Mortality Over 20 Years in the Trials of Hypertension Prevention. J Am Coll Cardiol. 2016;68(15):1609-1617. PubMed
  17. Mente A, O'Donnell M, Rangarajan S, et al. Associations of urinary sodium excretion with cardiovascular events in individuals with and without hypertension: a pooled analysis of data from four studies. Lancet. 2016;388(10043):465-75. PubMed
  18. Moosavian SP, Haghighatdoost F, Surkan PJ, Azadbakht L. Salt and obesity: a systematic review and meta-analysis of observational studies. Int J Food Sci Nutr. 2017;68(3):265-277. PubMed
  19. O'Donnell M, Mente A, Rangarajan S, et al. Urinary sodium and potassium excretion, mortality, and cardiovascular events. N Engl J Med. 2014;371(7):612-23. DOI
  20. Poggio R, Gutierrez L, Matta MG, Elorriaga N, Irazola V, Rubinstein A. Daily sodium consumption and CVD mortality in the general population: systematic review and meta-analysis of prospective studies. Public Health Nutr. 2015;18(4):695-704. PubMed
  21. Stallings VA, Harrison M, Oria M; Committee to Review the Dietary Reference Intakes for Sodium and Potassium, Food and Nutrition Board, Health and Medicine Division, National Academies of Sciences, Engineering, and Medicine. Washington (DC): National Acad
  22. Mahtani KR, Heneghan C, Onakpoya I, et al. Reduced Salt Intake for Heart Failure: A Systematic Review. JAMA Intern Med. 2018 Dec 1;178(12):1693-1700. PubMed
  23. Yancy CW. Sodium Restriction in Heart Failure: Too Much Uncertainty-Do the Trials. JAMA Intern Med. 2018 Dec 1;178(12):1700-1701. PubMed
  24. He FJ, Campbell NRC, Ma Y, MacGregor GA, Cogswell ME, Cook NR. Errors in estimating usual sodium intake by the Kawasaki formula alter its relationship with mortality: implications for public health. Int J Epidemiol. 2018;47(6):1784-1795. PubMed
  25. Murthy K, Ondrey GJ, Malkani N, et al. THE EFFECTS OF HYPONATREMIA ON BONE DENSITY AND FRACTURES: A SYSTEMATIC REVIEW AND META-ANALYSIS. Endocr Pract. 2019;25(4):366-378. PubMed
  26. Messerli FH, Hofstetter L, Syrogiannouli L, et al. Sodium intake, life expectancy, and all-cause mortality. Eur Heart J 2021;42(21):2103-2112. PubMed
  27. Graudal NA, Hubeck-Graudal T, Jurgens G. Effects of low sodium diet versus high sodium diet on blood pressure, renin, aldosterone, catecholamines, cholesterol, and triglyceride. Cochrane Database Syst Rev 2020;12(12):CD004022. PubMed
  28. Giatti S, Santos RB, Aielo AN, et al. Association of sodium with obstructive sleep apnea. The ELSA-Brasil study. Ann Am Thorac Soc 2021;18(3):502-510. PubMed
  29. Nan X, Lu H, Wu J, et al. The interactive association between sodium intake, alcohol consumption and hypertension among elderly in northern China: a cross-sectional study. BMC Geriatr 2021;21(1):135. PubMed
  30. Kyozuka H, Fukusda T, Murata T, et al. Impact of preconception sodium intake on hypertensive disorders of pregnancy: The Japan Environment and Children's study. Pregnancy Hypertens 2021;23:66-72. PubMed
  31. Zhao L, Ogden CL, Yang Q, et al. Association of usual sodium intake with obesity among US children and adolescents, NHANES 2009-2016. Obesity (Silver Spring) 2021;29(3):587-594. PubMed
  32. Ma Y, He FJ, Sun Q, et al. 24-Hour urinary sodium and potassium excretion and cardiovascular risk. N Engl J Med 2022;386(3):252-263. PubMed
  33. Liu J, Yang X, Zhang P, et al. Association of urinary sodium excretion and left ventricular hypertrophy in people with type 2 diabetes mellitus: A cross-sectional study. Front Endocrinol (Lausanne) 2021;12:728493. PubMed
  34. Filippini T, Malavolti M, Whelton PK, Vinceti M. Sodium intake and risk of hypertension: A systematic review and dose-response meta-analysis of observational cohort studies. Curr Hypertens Rep 2022;24(5):133-144. PubMed
  35. Wang DD, Li Y, Nguyen XT, et al. Dietary sodium and potassium intake and risk of non-fatal cardiovascular diseases: The million veteran program. Nutrients 2022;14(5):1121. PubMed
  36. Kwak JH, Park CH, Eun CS, et al. The associations of dietary intake of high sodium and low zinc with gastric cancer mortality: A prospective cohort study in Korea. Nutr Cancer 2022;74(10):3501-3508. PubMed
  37. George S, Maiti R, Mishra BR, Jena M, Mohapatra D. Effect of regulated add-on sodium chloride intake on stabilization of serum lithium concentration in bipolar disorder: A randomized controlled trial. Bipolar Disord 2023;25(1):66-75. PubMed
  38. Zhou TL, Schütten MTJ, Kroon AA, et al. Urinary Sodium Excretion and Salt Intake Are Not Associated With Blood Pressure Variability in a White General Population. J Am Heart Assoc 2023;12(1):e026578. PubMed

See these in context on the Sodium monograph →

Calcium 62 references
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  11. Chan JM, Giovannucci E, Andersson SO, et al. Dairy products, calcium, phosphorous, vitamin D, and risk of prostate cancer. Cancer Causes Control 1998;9:559-66.
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See these in context on the Calcium monograph →

Vitamin D 26 references
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  2. Tatro DS, ed. Drug Interactions Facts. Facts and Comparisons Inc., St. Louis, MO. 1999.
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  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.
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  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
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  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
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  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
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See these in context on the Vitamin D monograph →

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

See these in context on the Vitamin K monograph →

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

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

© 2021 Therapeutic Research Center, LLC

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