High Potency B1 100 mg Ingredients & Drug Interactions
What is this page for?
First and foremost: checking High Potency B1 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
High Potency B1 100 mg is a dietary supplement by Sundown Naturals 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 High Potency B1 100 mg by Sundown Naturals
Ask about any prescription or over-the-counter medication and we check it for interactions with High Potency B1 100 mg by Sundown Naturals — 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 High Potency B1 100 mg by Sundown Naturals
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 (vitamin B1) at 100 mg per tablet. Thiamine is an essential B vitamin your body needs to convert food into energy and keep your nerves working properly.
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 is effective for treating thiamine deficiency and Wernicke-Korsakoff syndrome, a serious neurological condition caused by severe thiamine lack. The evidence also suggests it may be possibly effective for period pain (dysmenorrhea).
For other uses listed — mosquito repellent and heart failure — the evidence suggests thiamine is possibly ineffective.
How safe is it?
Well-documented data
Thiamine is generally very well tolerated when taken by mouth in normal amounts. Rarely, it might cause skin reactions or allergic reactions; injected thiamine can very occasionally trigger more serious allergic responses, but this is uncommon with oral tablets.
Thiamine is needed during pregnancy and breastfeeding, and supplementing is likely safe — but use only the amounts your doctor or pharmacist advises rather than megadoses, since pregnancy and nursing have their own specific needs.
Meds to double-check
Minor interactions only
If you take trimethoprim (Proloprim), check with your doctor or pharmacist before starting this product — trimethoprim can increase how much thiamine your body retains. No interactions are documented in our data for the ingredients we could check with any other major drug categories.
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.
This B1 supplement works well if you have a thiamine deficiency or Wernicke-Korsakoff syndrome and is safe for most people at normal doses. If you take trimethoprim (an antibiotic), you'll want to check with your doctor or pharmacist before starting, since it may raise your thiamine level.
Either way, talk it over with your healthcare provider before adding it to your routine, especially if you're pregnant, nursing, or on any prescription medications.
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 Feb 23, 2012.
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 High Potency B1 100 mg, straight from the product label.
| Brand | Sundown Naturals |
|---|---|
| Barcode (UPC) | 030768039851 |
| Net contents | 100 Tablet(s) |
| Market status | On market |
| Date entered into DSLD | Feb 23, 2012 |
| DSLD ID | 6095 |
| Product type | Vitamin |
| Supplement form | Tablet Or Pill |
| Dietary claims / uses | Nutrient, All Other, Structure/Function |
| Intended target group(s) | Vegetarian, Adult (18 - 50 Years), Gluten Free, Sugar 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 High Potency B1 100 mg by Sundown Naturals, 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)
2010
General
Prod. No. 48708 05F B17590 FAZ
General Statements
Promotes Energy Metabolism*
Smart Facts As a B Vitamin, Thiamin (Vitamin B-1) plays a role in energy metabolism and nervous system function.*
Thiamin
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.
TAMPER RESISTANT: DO NOT USE IF SEAL UNDER CAP IS BROKEN OR MISSING.
KEEP OUT OF REACH OF CHILDREN.
Formulation
VEGETARIAN FORMULA
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.
Seals/Symbols
GUARANTEED QUALITY LABORATORY TESTED
PLEASE RECYCLE
FDA Statement of Identity
VITAMIN SUPPLEMENT
Suggested/Recommended/Usage/Directions
DIRECTIONS: FOR ADULTS, TAKE ONE (1) TABLET DAILY, PREFERABLY WITH A MEAL. As a reminder, discuss the supplements and medications you take with your health care providers.
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.
Storage
STORE IN A DRY PLACE AND AVOID EXCESSIVE HEAT.
Formula
HIGH POTENCY B1 100 MG
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
High Potency B1 100 mg by Sundown Naturals 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 High Potency B1 100 mg by Sundown Naturals
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.
High Potency B1 100 mg by Sundown Naturals Drug Interactions
HelloPharmacist Interaction Report
Sundown Naturals High Potency B1 contains thiamine, which has a documented interaction with trimethoprim (Proloprim), an antibiotic.
Trimethoprim may increase blood levels of thiamine by blocking the body's natural transporters that usually control how much thiamine gets into your bloodstream. This interaction is rated Minor in severity.
Read the full breakdown — every affected drug type, severity by severity
Although only one drug type shows an interaction in our data, the mechanism affects multiple transporters in your intestines, liver, and kidneys — which is why trimethoprim's effect on thiamine levels is measurable. If you take trimethoprim, your thiamine level might climb higher than expected, though this is unlikely to cause harm at standard supplement doses.
Altogether, these interactions span 3 individual medications. Use the medication checker below to search your exact drugs before you start, especially if you're on any form of trimethoprim.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against High Potency B1 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 High Potency B1 100 mg interact with 3 drugs. Click any drug to see the details.
1 of the 1 ingredient in High Potency B1 100 mg interact with drugs. Each result below shows which ingredient is responsible. Thiamine
Sulfadiazine, TrimethoprimCoptin
How Sulfadiazine, Trimethoprim interacts with High Potency B1 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 High Potency B1 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 High Potency B1 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 High Potency B1 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 High Potency B1 100 mg, from the product label.
High Potency B1 100 mg by Sundown Naturals: Common Questions
Does High Potency B1 100 mg by Sundown Naturals interact with any medications?
How can one product interact with so many drugs?
Where does this information come from?
Is this safe to take while pregnant or breastfeeding?
Can thiamine really help keep mosquitoes away?
What is thiamine used for?
Are there any side effects?
Does this product have any fillers?
I take trimethoprim for a UTI. Can I use this B1 supplement?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Not sure if High Potency B1 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 High Potency B1 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
High Potency B1 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