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Dietary supplement

Vitamin B2 Riboflavin Capsules 400 mg Ingredients & Drug Interactions

by BulkSupplements.com

Vitamin B2 Riboflavin Capsules 400 mg label
See full label image
Capsule Category: Vitamin
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 30, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Vitamin B2 Riboflavin Capsules 400 mg 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: Moderate

Vitamin B2 Riboflavin Capsules 400 mg is a dietary supplement by BulkSupplements.com with 1 active ingredient. Its ingredients are commonly taken for riboflavin deficiency, migraine prevention, general energy and metabolism support.Based on those ingredients, 20 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Riboflavin. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Vitamin B2 Riboflavin Capsules 400 mg by BulkSupplements.com

Ask about any prescription or over-the-counter medication and we check it for interactions with Vitamin B2 Riboflavin Capsules 400 mg by BulkSupplements.com — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Vitamin B2 Riboflavin Capsules 400 mg by BulkSupplements.com

Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Jul 11, 2026

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 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: 400 mg of riboflavin (vitamin B2), an essential B vitamin your body needs to convert food into energy and keep your cells healthy. The capsule itself is made from bovine gelatin.

Does it work?

Couldn't assess
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
Not assessable

This is a single-ingredient Riboflavin product and its label doesn't state a use — see Riboflavin's own graded uses on its monograph.

Why this rating?
  • We looked at the product name, claims, and label statements and couldn't find a stated purpose to grade.

Our data does not include an effectiveness rating for riboflavin for any specific health purpose. If you're considering this supplement for a particular reason, talk with your pharmacist about what the evidence actually supports.

The evidence, ingredient by ingredient Riboflavin

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.

Riboflavin is generally very well tolerated. Your body gets rid of excess riboflavin through your urine, so overdose is not a typical concern.

At this 400 mg dose, the most common side effects are dose-related nausea and bright yellow urine discoloration—both harmless. A small number of people in trials have reported diarrhea or increased urination at this dose level.

Riboflavin is needed during pregnancy and breastfeeding and is considered safe at recommended amounts. Since this is a high-dose supplement, check with your doctor or midwife before taking it while pregnant or nursing.

Side effects, ingredient by ingredient Riboflavin

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 — Riboflavin.
  • The most serious interaction on file is rated Moderate.
  • For scale: 20 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 tetracycline antibiotics (such as doxycycline or tetracycline itself), check with your pharmacist before starting this product. Riboflavin may theoretically reduce how well these antibiotics work, though this hasn't been confirmed in humans.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with no assessable stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

If you take a tetracycline antibiotic, ask your pharmacist before starting this product. Otherwise, riboflavin at this dose is generally well tolerated.

Expect bright yellow urine—that's normal and harmless. If nausea or other side effects bother you, your pharmacist can help you adjust.

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 Mar 25, 2025.

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 B2 Riboflavin Capsules 400 mg, straight from the product label.

Brand BulkSupplements.com
Barcode (UPC) X003XLOK0P
Net contents 180 Capsule(s)
Market status On market
Date entered into DSLD Mar 25, 2025
DSLD ID 330097
Product type Vitamin
Supplement form Capsule
Dietary claims / uses Nutrient, All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), 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 Vitamin B2 Riboflavin Capsules 400 mg by BulkSupplements.com, 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 Capsule(s)
Maximum serving Sizes:
1 Capsule(s)
Servings per container
180
UPC/BARCODE
X003XLOK0P
IngredientAmount% DV
Riboflavin400 mg30769%

Other ingredients: Bovine Gelatin

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

Vitamin B2 Riboflavin Capsules 400 mg per serving

Suggested/Recommended/Usage/Directions

Suggested use: As a dietary supplement, take 1 capsule once daily, or as directed by a physician.

Formulation

Free of: Added sugar, soy, dairy, yeast, gluten, additives

Storage

Store in a dry, cool place.

General Statements

Scan Me

New

FDA Disclaimer Statement

Warning: This product is not intended to diagnose, treat, cure, or prevent any disease.

Precautions

Always consult a physician before taking any dietary supplement.

Keep out of reach of children.

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

See for yourself

Vitamin B2 Riboflavin Capsules 400 mg by BulkSupplements.com label

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

Vitamin B2 Riboflavin Capsules 400 mg 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 Vitamin B2 Riboflavin Capsules 400 mg by BulkSupplements.com

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

Serving size1 Capsule(s) Dosage formCapsule Servings per container180 Amounts shown are per serving.

Riboflavin

Interacts with
20 drugs
400 mg per serving Form: Vitamin B2

Riboflavin (vitamin B2) is an essential nutrient your body needs to turn food into energy and to keep skin, eyes, and nerves healthy. It is generally...

Riboflavin monograph & interactions

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

Interaction report

Vitamin B2 Riboflavin Capsules 400 mg by BulkSupplements.com Drug Interactions

Want to check YOUR meds against Vitamin B2 Riboflavin Capsules 400 mg?

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
20Drugs
20 Moderate

Ingredients driving the most interactions

Riboflavin 20

Individual Drug Interactions

The ingredients in Vitamin B2 Riboflavin Capsules 400 mg interact with 20 drugs. Click any drug to see the details.

1 of the 1 ingredient in Vitamin B2 Riboflavin Capsules 400 mg interact with drugs. Each result below shows which ingredient is responsible. Riboflavin

Each ingredient & the kinds of drugs it affects

For each ingredient in Vitamin B2 Riboflavin Capsules 400 mg 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.

Riboflavin1 drug type · 20 drugs

Tetracycline Antibiotics

Theoretically, taking riboflavin with tetracycline antibiotics may decrease the potency of these antibiotics.
In vitro research suggests that riboflavin may inhibit the potency of tetracycline antibiotics. It is not clear if this effect is clinically significant, as this interaction has not been reported in humans.

Likelihood Possible Evidence D
Riboflavin full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Vitamin B2 Riboflavin Capsules 400 mg, from the product label.

BulkSupplements.com

See all BulkSupplements.com products
Name
BulkSupplements.com
Street Address
7511 Eastgate Rd
City
Henderson
State
NV
ZipCode
89011
Web Address
BulkSupplements.com
Pharmacist Counseling Corner

Vitamin B2 Riboflavin Capsules 400 mg by BulkSupplements.com: Common Questions

Does Vitamin B2 Riboflavin Capsules 400 mg by BulkSupplements.com interact with any medications?
Yes. Based on its ingredients, Vitamin B2 Riboflavin Capsules 400 mg has a known interaction with 20 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Vitamin B2 Riboflavin Capsules 400 mg 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 this turn my urine yellow?
Yes. High doses of riboflavin commonly cause bright yellow urine. This is completely harmless—it just means your body is excreting the excess riboflavin it doesn't need.
Can I take this while pregnant or breastfeeding?
Riboflavin is needed during pregnancy and breastfeeding. At recommended doses it's safe, but this is a 400 mg high-dose supplement, so check with your doctor before taking it to make sure the dose is right for you.
What are the side effects?
Riboflavin at this dose is generally well tolerated. The most common side effect is dose-related nausea. A small number of people have reported diarrhea or increased urination. The bright yellow urine is not a side effect—it's normal.
Is riboflavin safe if I take it long-term?
Yes. Riboflavin is very safe because your body simply removes excess amounts through your urine. There's no toxicity concern at high doses.
I'm on an antibiotic—can I take this?
If it's a tetracycline antibiotic like doxycycline, check with your pharmacist first. Riboflavin might reduce how well it works, though we don't know how much of a real-world problem that is.

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

Not sure if Vitamin B2 Riboflavin Capsules 400 mg 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.

Vitamin B2 Riboflavin Capsules 400 mg label
Go deeper

The Full Monographs Behind Vitamin B2 Riboflavin Capsules 400 mg’s Ingredients

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

Herb & supplement monograph

Riboflavin

Interacts with 20 drugs

Riboflavin (vitamin B2) is an essential nutrient your body needs to turn food into energy and to keep skin, eyes, and nerves healthy. It is generally very safe at typical doses, and the stro...

Read the full Riboflavin monograph →
Sources

Sources & How We Checked

Vitamin B2 Riboflavin Capsules 400 mg'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 5 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.

Riboflavin 5 references
  1. Schoenen J, Jacquy J, Lenaerts M. Effectiveness of high-dose riboflavin in migraine prophylaxis. A randomized controlled trial. Neurology 1998;50:466-70. PubMed
  2. Yates AA, Schlicker SA, Suitor CW. Dietary reference intakes: The new basis for recommendations for calcium and related nutrients, B vitamins, and choline. J Am Diet Assoc 1998;98:699-706. PubMed
  3. Leeson LJ, Weidenheimer JF. Stability of tetracycline and riboflavin. J Pharm Sci. 1969;58(3):355-7. PubMed
  4. MacLennan, S. C., Wade, F. M., Forrest, K. M., Ratanayake, P. D., Fagan, E., and Antony, J. High-dose riboflavin for migraine prophylaxis in children: a double-blind, randomized, placebo-controlled trial. J Child Neurol. 2008;23(11):1300-1304.
  5. Dietary reference intakes (DRIs): estimated average requirements. Food and Nutrition Board, Institute of Medicine, National Academics. https://www.nal.usda.gov/sites/default/files/fnic_uploads//recommended_intakes_individuals.pdf Accessed July 24, 2017.

See these in context on the Riboflavin 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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