B-1 100 mg Ingredients & Drug Interactions
What is this page for?
First and foremost: checking B-1 100 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
B-1 100 mg is a dietary supplement by Vitamin World with 1 active ingredient. Its ingredients are commonly taken for preventing or treating thiamine deficiency, beriberi, wernicke-korsakoff syndrome (alcohol-related).Based on those ingredients, 3 medications have a known interaction with it, the most serious rated minor. The ingredients most likely to interact are Thiamine. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.
Check Your Meds Against B-1 100 mg by Vitamin World
Ask about any prescription or over-the-counter medication and we check it for interactions with B-1 100 mg by Vitamin World — 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 B-1 100 mg by Vitamin World
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: thiamine (also called vitamin B1), at a dose of 100 mg per tablet. Thiamine is a water-soluble B vitamin your body uses to break down carbohydrates and support nerve and muscle function.
The tablet also contains several inactive ingredients — dicalcium phosphate, vegetable cellulose, stearic acid, silica, and vegetable magnesium stearate — which are fillers and binders that hold the tablet together.
Does it work?
Strong evidence
Thiamine at this dose is effective for treating thiamine deficiency and for Wernicke-Korsakoff syndrome (WKS), a serious neurological condition caused by severe thiamine shortage. It is possibly effective for dysmenorrhea (menstrual cramps).
The data shows it is possibly ineffective as a mosquito repellent and for heart failure.
How safe is it?
Well-documented data
Thiamine is generally very well tolerated when taken by mouth at normal doses. Allergic reactions and dermatitis (skin inflammation) are rare, though they can happen.
If you receive thiamine by injection (not this oral form), very rare serious allergic reactions are possible, but this tablet poses no such risk. Thiamine is needed during pregnancy and breastfeeding, and supplements are considered likely safe when taken at recommended doses under your doctor's or pharmacist's guidance.
If you are pregnant or nursing and considering this supplement, talk with your provider about what dose is right for you.
Meds to double-check
Minor interactions only
If you take trimethoprim (Proloprim), an antibiotic used for certain infections, let your pharmacist know before you start this supplement — it may raise your thiamine blood levels slightly. No interactions are documented with other common medication types in our data, but check your exact medications with the tool on this page.
The bottom line
Scorecard at a glanceFully disclosed formula with clinical evidence supporting its stated purpose. Only minor medication interactions are documented, and safety information is well characterized.
If you have a diagnosed thiamine deficiency or Wernicke-Korsakoff syndrome, this supplement can help. If you take trimethoprim (Proloprim) for an infection, check with your pharmacist before starting.
This is a straightforward, well-tolerated supplement — just make sure it's not going to interact with any medications you're on.
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 Oct 26, 2011.
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 B-1 100 mg, straight from the product label.
| Brand | Vitamin World |
|---|---|
| Barcode (UPC) | 074312716706 |
| Net contents | 100 Tablet(s) |
| Market status | On market |
| Date entered into DSLD | Oct 26, 2011 |
| DSLD ID | 590 |
| Product type | Vitamin |
| Supplement form | Tablet Or Pill |
| Dietary claims / uses | All Other, Structure/Function |
| Intended target group(s) | Vegetarian, Adult (18 - 50 Years) |
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 B-1 100 mg by Vitamin World, sourced from the NIH Dietary Supplement Label Database.
Supplement Facts
| Ingredient | Amount | % DV |
|---|---|---|
| Thiamine | 100 mg | 6667% |
Other ingredients: Dicalcium Phosphate, Vegetable Cellulose, Stearic Acid, Silica, Vegetable Magnesium Stearate
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.
Brand IP Statement(s)
©2008 Vitamin World, Inc.
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.
Formulation
No Artificial Color, Flavor or Sweetener, No Preservatives, No Sugar, No Starch, No Milk, No Lactose, No Soy, No Gluten, No Wheat, No Yeast, No Fish. Sodium Free.
Vegetarian Vitamin Supplement
Precautions
WARNING: If you are pregnant, nursing or taking any medications, consult your doctor before use. Discontinue use and consult your doctor if any adverse reactions occur. Keep out of reach of children. Store in a cool, dry place. Do not use if seal under cap is broken or missing.
General
PROD. #1670 B17590 08E
General Statements
Promotes Energy Metabolism*
Supports Nervous System Health*
Vitamin World products are subject to critically stringent quality assurance analysis. Our state-of-the-art laboratory, manufacturing and packaging facilities insure the highest quality nutritional supplements money can buy. Your health & safety are our first priority!
Get healthy.
Seals/Symbols
QUALITY ASSURED
Suggested/Recommended/Usage/Directions
DIRECTIONS: For adults, take one (1) to two (2) tablets daily, preferably with a meal.
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
B-1 100 mg by Vitamin World 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 B-1 100 mg by Vitamin World
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.
Thiamine
Interacts with3 drugs
Thiamine (vitamin B1) is an essential nutrient your body needs to turn food into energy and to keep your nerves and heart healthy. Most people get eno...
Thiamine monograph & interactionsOther (inactive) ingredients: Dicalcium Phosphate, Vegetable Cellulose, Stearic Acid, Silica, Vegetable Magnesium Stearate. These complete the product’s ingredient list but are not active constituents.
B-1 100 mg by Vitamin World Drug Interactions
HelloPharmacist Interaction Report
Vitamin World's B-1 100 mg contains thiamine, which has a documented interaction with one antibiotic.
Trimethoprim (Proloprim), used to treat certain infections, may increase blood levels of thiamine by slowing how your body clears it through the kidneys and liver. This is a Minor interaction — it means the drug changes how thiamine works in your body, but the clinical significance is small.
Read the full breakdown — every affected drug type, severity by severity
Although thiamine interacts with trimethoprim, no interactions are documented with other common medication types in our data. Altogether, these interactions span 3 individual medications.
If you take trimethoprim or any other prescription medication, run it through the checker below before starting this supplement to catch anything we may not have on file.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against B-1 100 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 checkerIngredients driving the most interactions
Individual Drug Interactions
The ingredients in B-1 100 mg interact with 3 drugs. Click any drug to see the details.
1 of the 1 ingredient in B-1 100 mg interact with drugs. Each result below shows which ingredient is responsible. Thiamine
Sulfadiazine, TrimethoprimCoptin
How Sulfadiazine, Trimethoprim interacts with B-1 100 mg — through 1 ingredient. Tap an ingredient for the detail:
ThiamineTrimethoprim (proloprim) Minor
Interaction Summary
Trimethoprim might increase blood levels of thiamine.
Read the full Thiamine + Sulfadiazine, Trimethoprim interactionSulfamethoxazole, TrimethoprimBactrim, Bactrim DS, Bactrim IV, Cotrim, Cotrim DS, Cotrimix +9 more
How Sulfamethoxazole, Trimethoprim interacts with B-1 100 mg — through 1 ingredient. Tap an ingredient for the detail:
ThiamineTrimethoprim (proloprim) Minor
Interaction Summary
Trimethoprim might increase blood levels of thiamine.
Read the full Thiamine + Sulfamethoxazole, Trimethoprim interactionTrimethoprimProloprim, Trimpex
How Trimethoprim interacts with B-1 100 mg — through 1 ingredient. Tap an ingredient for the detail:
ThiamineTrimethoprim (proloprim) Minor
Interaction Summary
Trimethoprim might increase blood levels of thiamine.
Read the full Thiamine + Trimethoprim interactionEach ingredient & the kinds of drugs it affects
For each ingredient in B-1 100 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.
Thiamine
Trimethoprim (Proloprim)
Trimethoprim might increase blood levels of thiamine.
In vitro, animal, and clinical research suggest that trimethoprim inhibits intestinal thiamine transporter ThTR-2, hepatic transporter OCT1, and renal transporters OCT2, MATE1, and MATE2, resulting in paradoxically increased thiamine plasma concentrations.
Brand information
Manufacturer and brand details for B-1 100 mg, from the product label.
Vitamin World
See all Vitamin World products- Phone Number
- 1-800-228-4533
- Web Address
- www.vitaminworld.com
B-1 100 mg by Vitamin World: Common Questions
Does B-1 100 mg by Vitamin World interact with any medications?
How can one product interact with so many drugs?
Where does this information come from?
Is thiamine safe to take if I'm pregnant or breastfeeding?
Can this supplement actually help with menstrual cramps?
What is thiamine used for?
Are there any side effects from taking thiamine?
Does this product have a lot of fillers?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Not sure if B-1 100 mg is safe with your meds?
Our pharmacists answer your medication & supplement questions — free.
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 B-1 100 mg’s Ingredients
Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.
Sources & How We Checked
B-1 100 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.
- 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 7 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.
Thiamine 7 references
- McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
- 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
- Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline (2000). Washington, DC: National Academy Press, 2000. Available at: http://b
- Rogovik, A. L., Vohra, S., and Goldman, R. D. Safety considerations and potential interactions of vitamins: should vitamins be considered drugs? Ann.Pharmacother. 2010;44(2):311-324. PubMed
- Arruti N, Bernedo N, Audicana MT, Villarreal O, Uriel O, Muñoz D. Systemic allergic dermatitis caused by thiamine after iontophoresis. Contact Dermatitis. 2013 Dec;69(6):375-6. PubMed
- Thiamine hydrochloride injection package insert. Lake Zurich, IL: Fresenius Kabi, LLC; September 2019.
- Vora B, Wen A, Yee SW, et al. The Effect of Trimethoprim on Thiamine Absorption: A Transporter-Mediated Drug-Nutrient Interaction. Clin Pharmacol Ther 2023;114(2):381-392.
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