Liquid Vitamin D-3 Ingredients & Drug Interactions
by NOW
What is this page for?
First and foremost: checking Liquid Vitamin D-3 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
Liquid Vitamin D-3 is a dietary supplement by NOW 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.
Check Your Meds Against Liquid Vitamin D-3 by NOW
Ask about any prescription or over-the-counter medication and we check it for interactions with Liquid Vitamin D-3 by NOW — and tell you which ingredient is responsible.
AI summaries are generated from our interaction database for education only — always confirm with your pharmacist. How we use AI
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HelloPharmacist Scorecard of Liquid Vitamin D-3 by NOW
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.
What’s inside
Full disclosure
This product contains one active ingredient: vitamin D. It's supplied in a liquid form, which can make dosing flexible, and is carried in medium chain triglyceride oil as an inactive ingredient.
Does it work?
Strong evidence
Vitamin D in this product is effective for treating rickets, familial hypophosphatemia, hypoparathyroidism, renal bone disease, and osteomalacia — conditions where the body cannot process or use calcium and phosphorus correctly. These are specialized medical uses, and vitamin D for these conditions should be prescribed and monitored by your doctor.
How safe is it?
Well-documented data
Vitamin D is generally well tolerated at recommended doses. Very high doses over time can cause toxicity, with symptoms including high blood calcium, weak bones in adults, slowed growth in children, eye inflammation, and light sensitivity.
Vitamin D is likely safe during pregnancy at recommended amounts, though some evidence flags possible concerns at very high doses — use only under your doctor's guidance. During breastfeeding, vitamin D at recommended doses is considered likely safe.
Meds to double-check
Moderate interaction found
Before taking this product, check with your pharmacist if you take verapamil, diltiazem, or digoxin (heart drugs) — high-dose vitamin D can make them less effective and digoxin poses arrhythmia risk. Also flag thiazide diuretics (water pills), atorvastatin (cholesterol), calcipotriene (psoriasis cream), or any drugs your liver breaks down via CYP3A4 enzymes.
If you have kidney failure and take aluminum-containing antacids, mention that too.
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.
If your doctor prescribed this for rickets, bone disease, or a parathyroid condition, it's effective — but vitamin D is a medication at prescription doses, not just a supplement. If you take heart rhythm drugs, water pills, cholesterol drugs, or use a vitamin D-like psoriasis cream, talk to your pharmacist or doctor before starting.
Stick to the doses your doctor recommends.
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 20, 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
General information
Key facts about Liquid Vitamin D-3, straight from the product label.
| Brand | NOW |
|---|---|
| Barcode (UPC) | 733739003706 |
| Net contents | 2 Fluid Ounce(s); 59 mL |
| Market status | On market |
| Date entered into DSLD | Jun 20, 2024 |
| DSLD ID | 314441 |
| Product type | Vitamin |
| Supplement form | Liquid |
| Dietary claims / uses | Nutrient, All Other, Structure/Function |
| Intended target group(s) | Children 4 or More Years of Age, Adult (18 - 50 Years), Kosher, Halal, Gluten Free, Dairy Free |
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 Liquid Vitamin D-3 by NOW, sourced from the NIH Dietary Supplement Label Database.
Supplement Facts
| Ingredient | Amount | % DV |
|---|---|---|
| Vitamin D | 10 mcg | 50% |
Other ingredients: Medium Chain Triglyceride Oil
Tap any ingredient to jump to its full detail below.
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
Suggested Usage: Shake well. For adults, take 4 drops 1 to 5 times daily. For children, administer 4 drops once daily. Do not exceed recommended dose. Take directly or add to your favorite beverage. If the dropper contacts the lips or oral tissues, thoroughly wash and dry it before replacing in the bottle and closing it completely. Best when taken with a fat-containing meal.
Formula
Each drop contains 100 IU of Vitamin D, 4 drops provide 400 IU, 20 drops provide 2,000 IU.
Triangle K (Kosher)
Crescent H (Halal)
Liquid Vitamin D-3 400 IU per 4 drops
Precautions
Caution: Keep out of reach of children. Not intended for use in infants. Give to children under 4 years old only under the direction of a pediatrician.
Consult physician if pregnant/nursing, taking medication, or have a medical condition.
Do not use if tamper evident band is damaged or missing. Discard if product changes color, becomes cloudy and/or a deposit appears on the liquid surface.
MCT Oil from coconut/palm kernel oil.
Not manufactured with yeast, wheat, gluten, soy, corn, milk, egg, fish, shellfish or sesame ingredients. Produced in a GMP facility that processes other ingredients containing these allergens.
Seals/Symbols
GMP Quality Assured
Triangle K (Kosher)
Crescent H (Halal)
Formulation
Structural support Helps maintain strong bones
Non-GMO
Made and quality tested in the USA with globally sourced ingredients.
Not manufactured with yeast, wheat, gluten, soy, corn, milk, egg, fish, shellfish or sesame ingredients.
FDA Statement of Identity
A Dietary Supplement
General Statements
Vitamins Family owned since 1968.
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.
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
Liquid Vitamin D-3 by NOW label
The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.
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)The Ingredients in Liquid Vitamin D-3 by NOW
This is the 1 active ingredient this product is made of. Select it to open its full monograph.
Serving size0.112 mL Dosage formLiquid Servings per container527 Amounts shown are per serving.
Vitamin D
Interacts with715 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,...
Vitamin D monograph & interactionsOther (inactive) ingredients: Medium Chain Triglyceride Oil. These complete the product’s ingredient list but are not active constituents.
Liquid Vitamin D-3 by NOW Drug Interactions
HelloPharmacist Interaction Report
NOW's Liquid Vitamin D-3 does interact with several medications, and the concern centers on high doses.
The most serious risk is with heart rhythm drugs: high-dose vitamin D can raise blood calcium levels (hypercalcemia), which reduces how well verapamil, diltiazem, and digoxin work, and with digoxin specifically can trigger dangerous heart arrhythmias. Stick to the safe upper limit of 4,000 IU daily for adults if you take any of these.
Read the full breakdown — every affected drug type, severity by severity
Vitamin D at high doses also interacts with thiazide water pills, which decrease how much calcium your body excretes — combined with vitamin D, this pushes calcium even higher. It may reduce how well atorvastatin (a cholesterol drug) is absorbed and lower its blood levels by up to 55%, though in one small study this didn't change cholesterol numbers.
Calcipotriene, a vitamin D-like psoriasis cream, adds to the hypercalcemia risk if you're also taking vitamin D supplements.
Vitamin D may also induce liver enzymes (CYP3A4 substrates) and slightly reduce the effectiveness of medications that depend on those enzymes. Additionally, in people with kidney failure, vitamin D might increase absorption of aluminum from other sources — a rare but serious concern.
Use the medication checker below to review your exact drugs before starting.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against Liquid Vitamin D-3?
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 checkerIngredients driving the most interactions
Individual Drug Interactions
The ingredients in Liquid Vitamin D-3 interact with 715 drugs. Click any drug to see the details.
1 of the 1 ingredient in Liquid Vitamin D-3 interact with drugs. Each result below shows which ingredient is responsible. Vitamin D
Ado-trastuzumab EmtansineKadcyla
How Ado-trastuzumab Emtansine interacts with Liquid Vitamin D-3 — through 1 ingredient. Tap an ingredient for the detail:
Vitamin DCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.
Read the full Vitamin D + Ado-trastuzumab Emtansine interactionAbemaciclibVerzenio
How Abemaciclib interacts with Liquid Vitamin D-3 — through 1 ingredient. Tap an ingredient for the detail:
Vitamin DCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.
Read the full Vitamin D + Abemaciclib interactionAbiraterone
How Abiraterone interacts with Liquid Vitamin D-3 — through 1 ingredient. Tap an ingredient for the detail:
Vitamin DCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.
Read the full Vitamin D + Abiraterone interactionAbiraterone AcetateYonsa, Zytiga
How Abiraterone Acetate interacts with Liquid Vitamin D-3 — through 1 ingredient. Tap an ingredient for the detail:
Vitamin DCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.
Read the full Vitamin D + Abiraterone Acetate interactionAcalabrutinibCalquence
How Acalabrutinib interacts with Liquid Vitamin D-3 — through 1 ingredient. Tap an ingredient for the detail:
Vitamin DCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.
Read the full Vitamin D + Acalabrutinib interactionAcetaminophen, Aspirin, CaffeineExcedrin, Excedrin Extra Strength, Excedrin Migraine
How Acetaminophen, Aspirin, Caffeine interacts with Liquid Vitamin D-3 — through 1 ingredient. Tap an ingredient for the detail:
Vitamin DCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.
Read the full Vitamin D + Acetaminophen, Aspirin, Caffeine interactionAcetaminophen, Butalbital, CaffeineEsgic, Esgic Plus, Fiogesic, Fioricet, Repan, Tecnal +1 more
How Acetaminophen, Butalbital, Caffeine interacts with Liquid Vitamin D-3 — through 1 ingredient. Tap an ingredient for the detail:
Vitamin DCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.
Read the full Vitamin D + Acetaminophen, Butalbital, Caffeine interactionAcetaminophen, Butalbital, Caffeine, CodeineEsgic with Codeine, Fioricet w/ Codeine
How Acetaminophen, Butalbital, Caffeine, Codeine interacts with Liquid Vitamin D-3 — through 1 ingredient. Tap an ingredient for the detail:
Vitamin DCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.
Read the full Vitamin D + Acetaminophen, Butalbital, Caffeine, Codeine interactionAcetaminophen, Caffeine, Chlorpheniramine, Hydrocodone, PhenylephrineHycomine Compound
How Acetaminophen, Caffeine, Chlorpheniramine, Hydrocodone, Phenylephrine interacts with Liquid Vitamin D-3 — through 1 ingredient. Tap an ingredient for the detail:
Vitamin DCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.
Read the full Vitamin D + Acetaminophen, Caffeine, Chlorpheniramine, Hydrocodone, Phenylephrine interactionAcetaminophen, Caffeine, CodeineGesic C15, Gesic C30, Gesic C8, Lenoltec 1, Lenoltec 2, Lenoltec 3 +1 more
How Acetaminophen, Caffeine, Codeine interacts with Liquid Vitamin D-3 — through 1 ingredient. Tap an ingredient for the detail:
Vitamin DCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.
Read the full Vitamin D + Acetaminophen, Caffeine, Codeine interactionAcetaminophen, Caffeine, Codeine, SalicylamideCodalan No.1, Codalan No.2, Codalan No.3
How Acetaminophen, Caffeine, Codeine, Salicylamide interacts with Liquid Vitamin D-3 — through 1 ingredient. Tap an ingredient for the detail:
Vitamin DCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.
Read the full Vitamin D + Acetaminophen, Caffeine, Codeine, Salicylamide interactionAcetaminophen, Caffeine, DihydrocodeineDHC Plus, Panlor DC, Panlor SS
How Acetaminophen, Caffeine, Dihydrocodeine interacts with Liquid Vitamin D-3 — through 1 ingredient. Tap an ingredient for the detail:
Vitamin DCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.
Read the full Vitamin D + Acetaminophen, Caffeine, Dihydrocodeine interactionAcetaminophen, Caffeine, IsomethepteneMigralam
How Acetaminophen, Caffeine, Isometheptene interacts with Liquid Vitamin D-3 — through 1 ingredient. Tap an ingredient for the detail:
Vitamin DCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.
Read the full Vitamin D + Acetaminophen, Caffeine, Isometheptene interactionAcetaminophen, Caffeine, PyrilamineMidol Max Strength Menstrual
How Acetaminophen, Caffeine, Pyrilamine interacts with Liquid Vitamin D-3 — through 1 ingredient. Tap an ingredient for the detail:
Vitamin DCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.
Read the full Vitamin D + Acetaminophen, Caffeine, Pyrilamine interactionAcetaminophen, Chlorpheniramine Maleate, Dextromethorphan HbrVicks Formula 44M Cough, Cold & Flu Relief
How Acetaminophen, Chlorpheniramine Maleate, Dextromethorphan Hbr interacts with Liquid Vitamin D-3 — through 1 ingredient. Tap an ingredient for the detail:
Vitamin DCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.
Read the full Vitamin D + Acetaminophen, Chlorpheniramine Maleate, Dextromethorphan Hbr interactionAcetaminophen, Chlorpheniramine, Codeine, PhenylephrineColrex
How Acetaminophen, Chlorpheniramine, Codeine, Phenylephrine interacts with Liquid Vitamin D-3 — through 1 ingredient. Tap an ingredient for the detail:
Vitamin DCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.
Read the full Vitamin D + Acetaminophen, Chlorpheniramine, Codeine, Phenylephrine interactionAcetaminophen, Chlorpheniramine, DextromethorphanCoricidin II Extra Strength Cold and Flu
How Acetaminophen, Chlorpheniramine, Dextromethorphan interacts with Liquid Vitamin D-3 — through 1 ingredient. Tap an ingredient for the detail:
Vitamin DCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.
Read the full Vitamin D + Acetaminophen, Chlorpheniramine, Dextromethorphan interactionAcetaminophen, Chlorpheniramine, Dextromethorphan HydrobromideCoricidin HBP Maximum Strength Flu
How Acetaminophen, Chlorpheniramine, Dextromethorphan Hydrobromide interacts with Liquid Vitamin D-3 — through 1 ingredient. Tap an ingredient for the detail:
Vitamin DCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.
Read the full Vitamin D + Acetaminophen, Chlorpheniramine, Dextromethorphan Hydrobromide interactionAcetaminophen, Chlorpheniramine, Dextromethorphan, PhenylpropanolamineMulti Symptom Cold Relief
How Acetaminophen, Chlorpheniramine, Dextromethorphan, Phenylpropanolamine interacts with Liquid Vitamin D-3 — through 1 ingredient. Tap an ingredient for the detail:
Vitamin DCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.
Read the full Vitamin D + Acetaminophen, Chlorpheniramine, Dextromethorphan, Phenylpropanolamine interactionAcetaminophen, Chlorpheniramine, Dextromethorphan, PseudoephedrineChildren's Tylenol Cold Plus Cough, Tylenol Cold Ex Strength
How Acetaminophen, Chlorpheniramine, Dextromethorphan, Pseudoephedrine interacts with Liquid Vitamin D-3 — through 1 ingredient. Tap an ingredient for the detail:
Vitamin DCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.
Read the full Vitamin D + Acetaminophen, Chlorpheniramine, Dextromethorphan, Pseudoephedrine interactionAcetaminophen, Chlorpheniramine, Guaifenesin, Phenylephrine, SalicylamideRhinogesic GG
How Acetaminophen, Chlorpheniramine, Guaifenesin, Phenylephrine, Salicylamide interacts with Liquid Vitamin D-3 — through 1 ingredient. Tap an ingredient for the detail:
Vitamin DCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.
Read the full Vitamin D + Acetaminophen, Chlorpheniramine, Guaifenesin, Phenylephrine, Salicylamide interactionAcetaminophen, Chlorpheniramine, PhenylephrineAlka-Seltzer PLUS, Histex SR, Protid
How Acetaminophen, Chlorpheniramine, Phenylephrine interacts with Liquid Vitamin D-3 — through 1 ingredient. Tap an ingredient for the detail:
Vitamin DCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.
Read the full Vitamin D + Acetaminophen, Chlorpheniramine, Phenylephrine interactionAcetaminophen, Chlorpheniramine, Phenylephrine, SalicylamideRhinogesic, Rhinogesic JR
How Acetaminophen, Chlorpheniramine, Phenylephrine, Salicylamide interacts with Liquid Vitamin D-3 — through 1 ingredient. Tap an ingredient for the detail:
Vitamin DCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.
Read the full Vitamin D + Acetaminophen, Chlorpheniramine, Phenylephrine, Salicylamide interactionAcetaminophen, Chlorpheniramine, PhenylpropanolamineAlumadrine, Conex, Sinadrin Max Strength, Sinulin
How Acetaminophen, Chlorpheniramine, Phenylpropanolamine interacts with Liquid Vitamin D-3 — through 1 ingredient. Tap an ingredient for the detail:
Vitamin DCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.
Read the full Vitamin D + Acetaminophen, Chlorpheniramine, Phenylpropanolamine interactionAcetaminophen, Chlorpheniramine, Phenylpropanolamine, OpiumHista-Derfule
How Acetaminophen, Chlorpheniramine, Phenylpropanolamine, Opium interacts with Liquid Vitamin D-3 — through 1 ingredient. Tap an ingredient for the detail:
Vitamin DCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.
Read the full Vitamin D + Acetaminophen, Chlorpheniramine, Phenylpropanolamine, Opium interactionAcetaminophen, Chlorpheniramine, Phenylpropanolamine, PhenyltoloxamineNorel Plus
How Acetaminophen, Chlorpheniramine, Phenylpropanolamine, Phenyltoloxamine interacts with Liquid Vitamin D-3 — through 1 ingredient. Tap an ingredient for the detail:
Vitamin DCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.
Read the full Vitamin D + Acetaminophen, Chlorpheniramine, Phenylpropanolamine, Phenyltoloxamine interactionAcetaminophen, Chlorpheniramine, PseudoephedrineAlka-Seltzer PLUS Liquid Gels, Children's Tylenol Cold, Codimal, Comtrex, Extra Strength Tylenol Allergy Sinus, Lorsin +3 more
How Acetaminophen, Chlorpheniramine, Pseudoephedrine interacts with Liquid Vitamin D-3 — through 1 ingredient. Tap an ingredient for the detail:
Vitamin DCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.
Read the full Vitamin D + Acetaminophen, Chlorpheniramine, Pseudoephedrine interactionAcetaminophen, DextromethorphanTylenol Cough Ex Strength
How Acetaminophen, Dextromethorphan interacts with Liquid Vitamin D-3 — through 1 ingredient. Tap an ingredient for the detail:
Vitamin DCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.
Read the full Vitamin D + Acetaminophen, Dextromethorphan interactionAcetaminophen, Dextromethorphan, Doxylamine, PseudoephedrineVicks NyQuil
How Acetaminophen, Dextromethorphan, Doxylamine, Pseudoephedrine interacts with Liquid Vitamin D-3 — through 1 ingredient. Tap an ingredient for the detail:
Vitamin DCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.
Read the full Vitamin D + Acetaminophen, Dextromethorphan, Doxylamine, Pseudoephedrine interactionAcetaminophen, Dextromethorphan, Guaifenesin, PhenylephrineConar-A
How Acetaminophen, Dextromethorphan, Guaifenesin, Phenylephrine interacts with Liquid Vitamin D-3 — through 1 ingredient. Tap an ingredient for the detail:
Vitamin DCytochrome P450 3a4 (cyp3a4) Substrates Minor
Interaction Summary
Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.
Read the full Vitamin D + Acetaminophen, Dextromethorphan, Guaifenesin, Phenylephrine interactionEach ingredient & the kinds of drugs it affects
For each ingredient in Liquid Vitamin D-3 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 D
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.
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.
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.
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.
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.
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.
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.
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.
Brand information
Manufacturer and brand details for Liquid Vitamin D-3, from the product label.
NOW
See all NOW products- Name
- NOW FOODS
- Street Address
- 395 S. Glen Ellyn Rd.
- City
- Bloomingdale
- State
- IL
- ZipCode
- 60108
- Web Address
- nowfoods.com
Liquid Vitamin D-3 by NOW: Common Questions
Does Liquid Vitamin D-3 by NOW interact with any medications?
How can one product interact with so many drugs?
Where does this information come from?
Can I take this if I'm pregnant?
Can I take this while breastfeeding?
What does vitamin D actually do in this product?
Is this product safe at high doses?
What are the side effects?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Not sure if Liquid Vitamin D-3 is safe with your meds?
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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.
The Full Monographs Behind Liquid Vitamin D-3’s Ingredients
Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.
Sources & How We Checked
Liquid Vitamin D-3'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.
- NIH Dietary Supplement Label Database (DSLD) — The official product label on file for this supplement.
- Natural Medicines (Therapeutic Research Center) — Evidence-graded clinical reference behind the ingredient interaction data.
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
- McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
- Tatro DS, ed. Drug Interactions Facts. Facts and Comparisons Inc., St. Louis, MO. 1999.
- 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
- Bar-Or D, Yoel G. Calcium and calciferol antagonize effect of verapamil in atrial fibrillation. Br Med J 1981;282:1585-6.
- 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.
- Crowe M, Wollner L, Griffiths RA. Hypercalcemia following vitamin D and thiazide therapy in the elderly. Practitioner 1984;228:312-3.
- Parfitt AM. Thiazide-induced hypercalcemia in vitamin D-treated hypoparathyroidism. Ann Intern Med 1972;77:557-63. PubMed
- Thiazide diuretics and the risk of osteoporosis. Pharmacist's Letter/Prescriber's Letter 2003;19(11):191105.
- Moon J. The role of vitamin D in toxic metal absorption. J Am Coll Nutr 1994;13:559-64.
- 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.
- Adler AJ, Berlyne GM. Duodenal aluminum absorption in the rat: effect of vitamin D. Am J Physiol 1985;249:G209-13. PubMed
- 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
- 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
- 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
- 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
- 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
- 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
- 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
- Weiner M, Epstein FH. Signs and symptoms of electrolyte disorders. Yale J Biol Med. 1970;43(2):76-109.
- 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
- 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
- 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.
- 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
- 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
- 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
- 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
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