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Dietary supplement

Vitamin B2 100 mg Ingredients & Drug Interactions

by Natural Factors

Vitamin B2 100 mg label
See full label image
Tablet Or Pill Category: Vitamin
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Vitamin B2 100 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 100 mg is a dietary supplement by Natural Factors 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 100 mg by Natural Factors

Ask about any prescription or over-the-counter medication and we check it for interactions with Vitamin B2 100 mg by Natural Factors — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Vitamin B2 100 mg by Natural Factors

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: riboflavin (vitamin B2) at 100 mg per tablet. Riboflavin is a B vitamin your body needs to convert food into energy and to keep your nervous system, muscles, and eyes working properly.

The tablet also contains inactive ingredients — microcrystalline cellulose, stearic acid, silica, and a coating — that help hold the pill together and protect it.

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

We hold no graded evidence for this product's ingredients for its stated purpose.

Why this rating?
  • The label markets this product for: energy production and healthy vision skin hair.
  • We looked for evidence on: Riboflavin deficiency, Migraine prevention, Eye health, Skin health.
  • Our graded evidence for these ingredients doesn't cover that particular purpose.

We don't have effectiveness ratings on file for riboflavin in our data, so we can't tell you what the evidence shows about what this dose is used for. If you're considering it for a specific health goal, your pharmacist or doctor can fill you in on what the research 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 considered very safe; your body excretes excess amounts in the urine. When taken by mouth, it's generally well tolerated.

The most common side effects are dose-related nausea and bright yellow urine at higher doses. Rarely, diarrhea or increased urination have been reported, mostly at much higher doses (400 mg daily).

Riboflavin is needed during pregnancy and breastfeeding and is generally safe at recommended amounts. If you're pregnant or nursing and want to take a high-dose supplement like this one, check with your provider first.

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 minocycline), check with your pharmacist before adding this supplement — riboflavin may theoretically reduce how well they work, though this hasn't been confirmed in patients.

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.

Vitamin B2 100 mg is a straightforward B-vitamin supplement that's well tolerated by most people. If you take tetracycline antibiotics, run them through our interaction checker before you start.

For pregnancy, breastfeeding, or any specific health goal, talk with your pharmacist or doctor.

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 May 22, 2020.

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 100 mg, straight from the product label.

Brand Natural Factors
Barcode (UPC) 068958012155
Net contents 90 Tablet(s)
Market status On market
Date entered into DSLD May 22, 2020
DSLD ID 220214
Product type Vitamin
Supplement form Tablet Or Pill
Dietary claims / uses Nutrient, All Other, Structure/Function
Intended target group(s) Vegan, Vegetarian, Adult (18 - 50 Years), Gluten Free, Dairy Free, Sugar 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 100 mg by Natural Factors, 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
068958012155
IngredientAmount% DV
Riboflavin100 mg7692%

Other ingredients: Microcrystalline Cellulose, Stearic Acid, Silica, Coating

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.
Seals/Symbols

isura Non-GMO - Mass Spec Documentation Lab tested

Purity & Potency Guaranteed

Suggested/Recommended/Usage/Directions

Suggested Usage: 1 tablet per day or as directed by a health professional.

Precautions

Cautions: As with any supplement, consult your health professional before use if you are pregnant, breastfeeding, or trying to conceive, or if you are taking medication, have a medical condition, or anticipate a surgery.

Keep out of the reach of children.

Sealed for your protection. Do not use if seal is broken.

Formula

Riboflavin (vitamin b2) is essential to the metabolism of carbohydrates, fats and proteins, which contributes to an increased energy production level in the body. Riboflavin also helps maintain healthy vision, skin, hair and mucous membranes.

Riboflavin

Formulation

Manufactured by Natural Factors to ensure safety and potency in accordance with Good Manufacturing Practices (GMP) of the FDA and Health Canada.

Contains no artificial colors, preservatives, or sweeteners; no dairy, starch, sugar, wheat, gluten, yeast, soy, corn, egg, fish, shellfish, animal products, salt, tree nuts, or GMOs.

Suitable for vegetarian/vegans.

Storage

For freshness, store in a cool, dry place.

FDA Disclaimer Statement

This statement has not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

General Statements

Product of Canada Recyclable container and label.

FDA Statement of Identity

Dietary Supplement

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

See for yourself

Vitamin B2 100 mg by Natural Factors label

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

Vitamin B2 100 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 100 mg by Natural Factors

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.

Riboflavin

Interacts with
20 drugs
100 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: Microcrystalline Cellulose, Stearic Acid, Silica, Coating. These complete the product’s ingredient list but are not active constituents.

Interaction report

Vitamin B2 100 mg by Natural Factors Drug Interactions

Want to check YOUR meds against Vitamin B2 100 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 100 mg interact with 20 drugs. Click any drug to see the details.

1 of the 1 ingredient in Vitamin B2 100 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 100 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 100 mg, from the product label.

Natural Factors

See all Natural Factors products
Name
Natural Factors Canada
Pharmacist Counseling Corner

Vitamin B2 100 mg by Natural Factors: Common Questions

Does Vitamin B2 100 mg by Natural Factors interact with any medications?
Yes. Based on its ingredients, Vitamin B2 100 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 100 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?
At higher doses, riboflavin can cause bright yellow urine. At 100 mg, this is possible but not guaranteed. It's harmless and stops once you stop taking it.
Can I take this if I'm pregnant?
Riboflavin is needed during pregnancy and is generally safe at recommended amounts. If you want to take this 100 mg supplement during pregnancy, check with your doctor or midwife first.
Can I take this if I'm breastfeeding?
Riboflavin is needed while breastfeeding and is generally safe at recommended amounts. For a high-dose supplement like this, ask your provider.
What side effects might I get?
Most people tolerate riboflavin well. Dose-related nausea is the most common side effect at higher amounts. Diarrhea and increased urination are rare.
Is this supplement necessary if I eat a normal diet?
The facts on file don't tell us whether you need supplementation — that depends on your diet and health. Your pharmacist or doctor can advise whether this makes sense for you.

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

Not sure if Vitamin B2 100 mg 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 B2 100 mg label
Go deeper

The Full Monographs Behind Vitamin B2 100 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 100 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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