Interactions on record — worth a quick check against your medications. Check your meds →
Dietary supplement

Vitamin D 400 IU Ingredients & Drug Interactions

by SimplySupplements

Tablet Or Pill Category: Vitamin
Most serious interaction: Moderate
The interaction bottom line Most serious interaction: Moderate

Vitamin D 400 IU is a dietary supplement by SimplySupplements with 1 active ingredient. Its ingredients are commonly taken for bone health and osteoporosis, correcting vitamin d deficiency, immune system support.Based on those ingredients, 715 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Vitamin D. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

HelloPharmacist Scorecard of Vitamin D 400 IU by SimplySupplements

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

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 1 of its 1 active ingredient.
  • No proprietary blends here — you can verify the dose of every single component.

This product contains one active ingredient: vitamin D, supplied at 400 IU per tablet. Vitamin D is a fat-soluble vitamin your body uses to absorb calcium, support bone health, and regulate immune function.

The remaining ingredients—dicalcium phosphate, microcrystalline cellulose, magnesium stearate, and silicon dioxide—are inactive excipients that help form and preserve the tablet.

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 and vitamin D deficiency correction.
  • We looked for evidence on: Corticosteroid-induced osteoporosis, Fall prevention, Familial hypophosphatemia, Fractures, Hyperparathyroidism-related bone loss, Kidney transplant-related bone loss — and 4 related terms.
  • The strongest evidence on file: Vitamin D is rated "Effective" for Familial hypophosphatemia (Natural Medicines).
  • Also on file: Vitamin D is rated "Effective" for Osteomalacia, Renal osteodystrophy.
  • Also on file: Vitamin D is rated "Likely Effective" for Corticosteroid-induced osteoporosis.

Vitamin D at this dose is effective for preventing and treating rickets, osteomalacia (soft bones in adults), renal bone disease, and familial hypophosphatemia according to the research we hold. The evidence we have on file doesn't address whether 400 IU is sufficient for general bone health or immune support in otherwise healthy people—that's a question worth discussing with your doctor or pharmacist, since individual vitamin D needs vary widely.

The evidence, ingredient by ingredient Vitamin D

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 1 of the 1 matched ingredient.
  • Pregnancy & breastfeeding safety ratings cover 1 of 1.
  • General safety write-ups exist for 1 of 1.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Vitamin D is generally well tolerated at recommended doses. This 400 IU tablet is far below the threshold for toxicity.

However, very high doses taken over time can cause vitamin D toxicity, with symptoms like high blood calcium, bone loss, poor growth in children, and eye irritation. If you're pregnant or breastfeeding, use vitamin D only under your doctor's guidance.

The data on file doesn't specify how much is safe in pregnancy, so a conversation with your healthcare provider is important.

Side effects, ingredient by ingredient Vitamin D

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

The most serious documented interaction for these ingredients is Moderate. Check your medications for a personalized result.

Why this rating?
  • 1 of the 1 matched ingredient can interact with medications — Vitamin D.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: heart-rhythm medications.
  • For scale: 716 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

If you take digoxin (Lanoxin) or other heart rhythm drugs, thiazide diuretics, verapamil or diltiazem, atorvastatin (Lipitor), calcipotriene (Dovonex), or aluminum-containing antacids—especially if you have kidney problems—check your medications before using this product. Additionally, vitamin D may affect a large class of medications processed through the liver; run your full medication list through the checker on this page.

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. Moderate medication interactions have been identified, and safety information is well characterized.

Vitamin D 400 IU is a low-dose supplement suitable for general use and effective for treating specific vitamin D deficiency conditions. If you take heart rhythm medications, thiazide diuretics, calcium channel blockers, atorvastatin, or psoriasis treatments, or if you take aluminum supplements, check your medications with the tool below before starting.

A quick conversation with your pharmacist can confirm whether this product works with what you're taking.

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

Assessment coverage: 1 of 1 active ingredient matched to our full ingredient reviews (monographs). Based on the product label dated Jun 25, 2013.

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 Vitamin D 400 IU, straight from the product label.

Brand SimplySupplements
Barcode (UPC) 5060208412253
Net contents 180 Tablet(s)
Market status On market
Date entered into DSLD Jun 25, 2013
DSLD ID 22029
Product type Vitamin
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 Vitamin D 400 IU by SimplySupplements, 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 Tablet(s)
Maximum serving Sizes:
1 Tablet(s)
UPC/BARCODE
5060208412253
IngredientAmount% DV
Vitamin D400 IU200%

Other ingredients: Dicalcium Phosphate, Microcrystalline Cellulose, Magnesium Stearate, Silicon Dioxide

Tap any ingredient to jump to its full detail below.

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

S509

General Statements

AUTODESPATCH Save 10% by having your supplements conveniently scheduled and delivered automatically. SAME DAY DESPATCH We will ensure your order is despatched on the day of receipt (before 12.30pm) and that all orders after 12.30pm are despatched within 24 hours. All sent 1st class!

BUY ONE GET ONE FREE on everything!

PRICE MATCH GUARANTEE! Lowest Price in the UK or we will refund the difference plus 10%!

Seals/Symbols

SimplySupplements(TM) High Quality Vitamins & Minerals

Suggested/Recommended/Usage/Directions

DIRECTIONS For adults, take one tablet daily as a food supplement or as directed by a healthcare professional.

Storage

Store in a cool dry place.

Precautions

Do not use if the seal is broken. Do not exceed stated dose.

Keep away from children at all times.

Pregnant and Lactating women should consult a Doctor before use.

Food supplement: This product should not be used as a substitute for a varied diet. Caution: If under medical supervision please consult a Doctor before use. Discontinue use if adverse reactions occur.

See for yourself

Vitamin D 400 IU by SimplySupplements label

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

What’s inside

The Ingredients in Vitamin D 400 IU by SimplySupplements

This is the 1 active ingredient this product is made of. Select it to open its full monograph.

Serving size1 Tablet(s) Dosage formTablet Or Pill Amounts shown are per serving.

Vitamin D

Interacts with
715 drugs
400 IU per serving

Vitamin D is a fat-soluble vitamin that helps your body absorb calcium and is important for healthy bones, muscles, and immune function. Many people,...

Vitamin D monograph & interactions

Other (inactive) ingredients: Dicalcium Phosphate, Microcrystalline Cellulose, Magnesium Stearate, Silicon Dioxide. These complete the product’s ingredient list but are not active constituents.

Interaction report

Vitamin D 400 IU by SimplySupplements Drug Interactions

Want to check YOUR meds against Vitamin D 400 IU?

Ask about interactions with your drugs in plain English — “Can I take it with lisinopril?” — and we find you the answer in seconds, ingredient by ingredient.

Go to the checker
715Drugs
80 Moderate 635 Minor

Ingredients driving the most interactions

Vitamin D 715

Each ingredient & the kinds of drugs it affects

For each ingredient in Vitamin D 400 IU with known interactions, here are the types of medications it can affect. Open any type for the detail — or search your exact drug in the checker above.

Vitamin D8 drug types · 715 drugs

Aluminum

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

Likelihood Probable Evidence B
Atorvastatin (Lipitor)

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

Likelihood Probable Evidence B
Calcipotriene (Dovonex)

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

Likelihood Probable Evidence D
Digoxin (Lanoxin)

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

Likelihood Possible Evidence D
Diltiazem (Cardizem, Others)

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

Likelihood Probable Evidence B
Thiazide Diuretics

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

Likelihood Probable Evidence D
Verapamil (Calan, Others)

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

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

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

Likelihood Possible Evidence D
The maker

Brand information

Manufacturer and brand details for Vitamin D 400 IU, from the product label.

SimplySupplements

See all SimplySupplements products
Name
Simply Supplements
Street Address
PO Box 204
City
Guernsey
ZipCode
GY1 3NB
Pharmacist Counseling Corner

Vitamin D 400 IU by SimplySupplements: Common Questions

Does Vitamin D 400 IU by SimplySupplements interact with any medications?
Yes. Based on its ingredients, Vitamin D 400 IU has a known interaction with 715 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Vitamin D 400 IU contains a single active ingredient, and that one ingredient can interact with many different medications on its own. We check it against each medication and show the mechanism 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 400 IU of vitamin D work for my weak bones or vitamin D deficiency?
Vitamin D is effective for treating rickets, osteomalacia (soft bones in adults), bone disease linked to kidney problems, and familial hypophosphatemia. Whether 400 IU is the right dose for you depends on your blood vitamin D level and the condition being treated—that's a conversation to have with your doctor, since needs vary widely.
Is this safe to take while pregnant or breastfeeding?
Vitamin D is often used during pregnancy and breastfeeding at recommended amounts, but the exact dose should be guided by your doctor. We don't have detailed safety data for higher doses in pregnancy on file, so check with your healthcare provider before starting.
What are the side effects of vitamin D?
At the recommended dose of 400 IU, vitamin D is very well tolerated and side effects are unlikely. However, excessive doses over time can cause toxicity with symptoms like high blood calcium, weak bones, eye irritation, and poor growth in children. This dose is far below that threshold.
Can I take this with my blood pressure or heart medications?
It depends on which medications you take. High-dose vitamin D can raise blood calcium and interfere with heart rhythm drugs like digoxin, verapamil, and diltiazem—but this product supplies only 400 IU, well below the risky threshold. Still, use the medication checker on this page to be sure about your specific drugs.
Does vitamin D interact with cholesterol medications?
Vitamin D may reduce how well your body absorbs atorvastatin (Lipitor), though the research is limited. If you take it, run it through the checker on this page to see if your dose or timing needs adjustment.
What are the inactive ingredients in this tablet?
The tablet contains dicalcium phosphate, microcrystalline cellulose, magnesium stearate, and silicon dioxide—all standard excipients that help form and preserve the tablet. If you're sensitive to any of these, let us know.

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

Not sure if Vitamin D 400 IU is safe with your meds?

Our pharmacists answer your medication & supplement questions — free.

Ask a pharmacist

Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

Vitamin D 400 IU label
Sources

Sources & How We Checked

Vitamin D 400 IU'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 26 references behind this product’s interaction data

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

Vitamin D 26 references
  1. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
  2. Tatro DS, ed. Drug Interactions Facts. Facts and Comparisons Inc., St. Louis, MO. 1999.
  3. Koutkia P, Chen TC, Holick MF. Vitamin D intoxication associated with an over-the-counter supplement. N Engl J Med 2001;345:66-7. PubMed
  4. Bar-Or D, Yoel G. Calcium and calciferol antagonize effect of verapamil in atrial fibrillation. Br Med J 1981;282:1585-6.
  5. Demontis R, Leflon A, Fournier A, et al. 1 alpha(OH) vitamin D3 increases plasma aluminum in hemodialyzed patients taking AI(OH)3. Clin Nephrol 1986;26:146-9.
  6. Crowe M, Wollner L, Griffiths RA. Hypercalcemia following vitamin D and thiazide therapy in the elderly. Practitioner 1984;228:312-3.
  7. Parfitt AM. Thiazide-induced hypercalcemia in vitamin D-treated hypoparathyroidism. Ann Intern Med 1972;77:557-63. PubMed
  8. Thiazide diuretics and the risk of osteoporosis. Pharmacist's Letter/Prescriber's Letter 2003;19(11):191105.
  9. Moon J. The role of vitamin D in toxic metal absorption. J Am Coll Nutr 1994;13:559-64.
  10. Demontis R, Reissi D, Noel C, et al. Indirect clinical evidence that 1alphaOH vitamin D<SUB>3</SUB> increases the intestinal absorption of aluminum. Clin Nephrol 1989;31:123-7.
  11. Adler AJ, Berlyne GM. Duodenal aluminum absorption in the rat: effect of vitamin D. Am J Physiol 1985;249:G209-13. PubMed
  12. Schwartz JB. Effects of vitamin D supplementation in atorvastatin-treated patients: A new drug interaction with an unexpected consequence. Clin Pharmacol Ther 2009;85:198-203. PubMed
  13. Dietary reference intakes for calcium and vitamin D. Institute of Medicine, November 30, 2010. Available at: http://www.iom.edu/~/media/Files/Report%20Files/2010/Dietary-Reference-Intakes-for-Calcium-and-Vitamin-D/Vitamin%20D%20and%20Calcium%202010%20Repo
  14. Cox KA, Dunn MA. Aluminum toxicity alters the regulation of calbindin-D28k protein and mRNA expression in chick intestine. J Nutr 2001;131:2007-13. PubMed
  15. Escribano, J., Balaguer, A., Pagone, F., Feliu, A., and Roque, I. Figuls. Pharmacological interventions for preventing complications in idiopathic hypercalciuria. Cochrane.Database.Syst.Rev. 2009;(1):CD004754. PubMed
  16. Carlton, S., Clopton, D., and Cappuzzo, K. A. Vitamin D deficiency: appropriate replenishment therapies and the effects of vitamin D toxicity. Consult Pharm 2010;25(3):171-177. PubMed
  17. Wang, H., Xia, N., Yang, Y., and Peng, D. Q. Influence of vitamin D supplementation on plasma lipid profiles: a meta-analysis of randomized controlled trials. Lipids Health Dis. 2012;11:42. PubMed
  18. Turner AN, Carr Reese P, Fields KS, Anderson J, Ervin M, Davis JA, Fichorova RN, Roberts MW, Klebanoff MA, Jackson RD. A blinded, randomized controlled trial of high-dose vitamin D supplementation to reduce recurrence of bacterial vaginosis. Am J Obstet G PubMed
  19. Weiner M, Epstein FH. Signs and symptoms of electrolyte disorders. Yale J Biol Med. 1970;43(2):76-109.
  20. Lappe J, Watson P, Travers-Gustafson D, Recker R, Garland C, Gorham E, Baggerly K, McDonnell SL. Effect of Vitamin D and Calcium Supplementation on Cancer Incidence in Older Women: A Randomized Clinical Trial. JAMA. 2017 Mar 28;317(12):1234-1243. PubMed
  21. Roth DE, Leung M, Mesfin E, Qamar H, Watterworth J, Papp E. Vitamin D supplementation during pregnancy: state of the evidence from a systematic review of randomised trials. BMJ. 2017;359:j5237. PubMed
  22. Murai IH, Fernandes AL, Sales LP, et al. Effect of a single high dose of vitamin D3 on hospital length of stay in patients with moderate to severe COVID-19: A randomized clinical trial. JAMA. 2021.
  23. Wang Z, Schuetz EG, Xu Y, Thummel KE. Interplay between vitamin D and the drug metabolizing enzyme CYP3A4. J Steroid Biochem Mol Biol 2013;136:54-8. PubMed
  24. Doyle D, Browne U, Brickley A, Murphy D. Vitamin D-induced hypercalcaemia and acute kidney injury in sarcoidosis. BMJ Case Rep 2023;16(1):e250580. PubMed
  25. Williamson A, Martineau AR, Sheikh A, Jolliffe D, Griffiths CJ. Vitamin D for the management of asthma. Cochrane Database Syst Rev 2023;2(2):CD011511. PubMed
  26. Kinesya E, Santoso D, Gde Arya N, et al. Vitamin D as adjuvant therapy for diabetic foot ulcers: Systematic review and meta-analysis approach. Clin Nutr ESPEN 2023;54:137-143. PubMed

See these in context on the Vitamin D monograph →

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

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

© 2021 Therapeutic Research Center, LLC

Keep exploring