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Dietary supplement

B-1 100 mg Ingredients & Drug Interactions

by Superior Source

B-1 100 mg label
See full label image
Tablet Or Pill Category: Botanical With Nutrients
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 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

The interaction bottom line Most serious interaction: Moderate

B-1 100 mg is a dietary supplement by Superior Source with 2 active ingredients. Its ingredients are commonly taken for preventing or treating thiamine deficiency, beriberi, wernicke-korsakoff syndrome (alcohol-related).Based on those ingredients, 262 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Stevia leaf extract, Thiamine. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against B-1 100 mg by Superior Source

Ask about any prescription or over-the-counter medication and we check it for interactions with B-1 100 mg by Superior Source — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of B-1 100 mg by Superior Source

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 2 of its 2 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

This product contains 2 active ingredients. Thiamine (vitamin B-1) is an essential vitamin your body needs for energy production and nerve function.

Stevia leaf extract is a no-calorie sweetener derived from the stevia plant. The inactive ingredients — lactose, natural flavors, and acacia — are fillers and binders that make up the tablet.

Does it work?

Strong evidence
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
Strong

Clinical evidence supports at least one of this product's ingredients for its stated purpose.

Why this rating?
  • The label markets this product for: Thiamine B-vitamin supplementation and nutrition.
  • We looked for evidence on: Thiamine deficiency, Wernicke-Korsakoff syndrome (WKS), Energy metabolism, Nerve function support, General wellness.
  • The strongest evidence on file: Thiamine is rated "Effective" for Thiamine deficiency (Natural Medicines).
  • Also on file: Thiamine is rated "Effective" for Wernicke-Korsakoff syndrome (WKS).

Thiamine is effective for treating thiamine deficiency and Wernicke-Korsakoff syndrome, a serious brain condition caused by severe thiamine shortage. It's possibly effective for period pain (dysmenorrhea), though the evidence is limited.

For heart failure and as a mosquito repellent, thiamine is possibly ineffective based on available data. Stevia's effectiveness for diabetes, high blood pressure, and weight loss is unclear — we don't have enough reliable evidence to say whether it works for those uses.

The evidence, ingredient by ingredient Thiamine Stevia

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 2 of the 2 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 2 of 2.
  • General safety write-ups exist for 2 of 2.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Thiamine is generally very safe when taken by mouth in normal amounts. Serious side effects are rare — allergic reactions like skin rashes can happen but are uncommon.

The safety data supports thiamine in pregnancy and breastfeeding when used at recommended doses under your provider's guidance, since it's actually needed during those times. Purified stevia in food amounts is generally recognized as safe.

However, this product delivers stevia as a high-dose supplement, and long-term safety data for that form isn't well established, so caution is warranted. Minor side effects reported in studies — bloating, dizziness, headache, muscle pain, nausea, numbness — usually resolve after the first week.

Allergic reactions are rare.

Side effects, ingredient by ingredient Thiamine Stevia

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?
  • 2 of the 2 matched ingredients can interact with medications — Stevia, Thiamine.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: diabetes medications; lithium.
  • For scale: 262 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.

Check your medications if you take lithium — stevia may raise its levels dangerously (Moderate interaction). Also verify any trimethoprim antibiotics, blood pressure drugs, or diabetes medications, since stevia and thiamine have documented Minor interactions with those types.

Check your own medication Run your meds through the checker above

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.

This product is straightforward for most people who need a thiamine supplement and don't mind a stevia-sweetened tablet. If you take lithium, trimethoprim, blood pressure medications, or diabetes drugs, check with us or your doctor first.

Pregnant or breastfeeding? Thiamine is actually needed during those times, but talk with your provider about whether you need a supplement or can get enough from food.

Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI

Assessment coverage: 2 of 2 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Feb 24, 2017.

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 B-1 100 mg, straight from the product label.

Brand Superior Source
Net contents 100 MicroLingual(R) Instant Dissolve Tablet(s)
Market status On market
Date entered into DSLD Feb 24, 2017
DSLD ID 70857
Product type Botanical With Nutrients
Supplement form Tablet Or Pill
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years)
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 B-1 100 mg by Superior Source, 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 MicroLingual(R) Tablet(s)
Maximum serving Sizes:
1 MicroLingual(R) Tablet(s)
Servings per container
100
IngredientAmount% DV
Thiamine100 mg6670%
Stevia leaf extract2 mg--

Other ingredients: Lactose, Natural Flavors, Acacia

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.
General Statements

No shot

Our proprietary hydrodrying process results in fewer inactive binders and fillers and a higher ratio of nutritional ingredients - hence the small size. They efficiently provide your body with the nutrients you need right now.

"Less is more" Simplicity Purity Efficiency No pills to swallow

Dissolves immediately on contact

FDA Statement of Identity

Dietary Supplement

Brand IP Statement(s)

Our instant Dissolve MicroLingual Tablets may be small but they are full potency! Typical tablets and capsules need to be swallowed and are inefficiently absorbed in the digestive system. MicroLingual tablets dissolve immediately under the tongue heading straight into the body.

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.

Suggested/Recommended/Usage/Directions

Directions: As a dietary supplement, dissolve one MicroLingual tablet under the tongue as directed by your healthcare provider. This product may also be swallowed.

Place on or under the tongue

Formulation

Preservative free

Seals/Symbols

Made in USA

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

See for yourself

B-1 100 mg by Superior Source label

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

B-1 100 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 B-1 100 mg by Superior Source

These are the 2 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 MicroLingual(R) Tablet(s) Dosage formTablet Or Pill Servings per container100 Amounts shown are per serving.

Most supplement products combine several ingredients, and a medication can interact with the product through any one of them. Each ingredient below shows whether it has known drug interactions.

Thiamine

Interacts with
3 drugs
100 mg per serving Form: Thiamine Mononitrate, Vitamin B1

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 & interactions

Stevia leaf extract

Interacts with
259 drugs
2 mg per serving

Stevia is a plant-based, calorie-free sweetener that is widely used as a sugar alternative and is considered safe in normal food amounts by major regu...

Stevia leaf extract monograph & interactions

Other (inactive) ingredients: Lactose, Natural Flavors, Acacia. These complete the product’s ingredient list but are not active constituents.

Interaction report

B-1 100 mg by Superior Source Drug Interactions

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 checker
262Drugs
1 Moderate 261 Minor

Ingredients driving the most interactions

Stevia leaf extract 259
Thiamine 3

Individual Drug Interactions

The ingredients in B-1 100 mg interact with 262 drugs. Click any drug to see the details.

2 of the 2 ingredients in B-1 100 mg interact with drugs. Each result below shows which ingredient is responsible. Stevia leaf extract Thiamine

Each ingredient & the kinds of drugs it affects

For each ingredient in B-1 100 mg with known interactions, here are the types of medications they can affect. Open any type for the detail — or search your exact drug in the checker above.

Stevia leaf extract3 drug types · 259 drugs

Lithium

Theoretically, stevia might decrease clearance and increase levels of lithium.
Animal research suggests that stevia extracts might have diuretic activity. Theoretically, increased reabsorption of lithium along with sodium might reduce excretion and increase levels of lithium.

Likelihood Possible Evidence D
Antidiabetes Drugs

Theoretically, stevia might increase the risk for hypoglycemia when combined with antidiabetes drugs.
Preliminary clinical research in patients with type 2 diabetes suggests that taking a single dose of stevia extract 1000 mg reduces postprandial blood glucose levels when taken with a meal. However, other clinical research in patients with type 1 or type 2 diabetes suggests that taking stevioside 250 mg three times daily does not significantly affect blood glucose levels or glycated hemoglobin (HbA1C) after three months of treatment.

Likelihood Possible Evidence D
Antihypertensive Drugs

Theoretically, combining stevia or stevia constituents with antihypertensive agents might increase the risk of hypotension.
Stevia extract and stevioside might lower blood pressure in patients with hypertension. However, other clinical research suggests that stevioside does not significantly lower blood pressure in patients with hypertension.

Likelihood Possible Evidence D
Stevia leaf extract full monograph & interactions

Thiamine1 drug type · 3 drugs

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.

Likelihood Probable Evidence B
Thiamine full monograph & interactions
The maker

Brand information

Manufacturer and brand details for B-1 100 mg, from the product label.

Superior Source

See all Superior Source products
Name
Continental Vitamin Co. Superior Source
City
Los Angeles
State
CA
ZipCode
90058
Phone Number
(800) 421-6175
Web Address
www.superiorsource1.com
Pharmacist Counseling Corner

B-1 100 mg by Superior Source: Common Questions

Does B-1 100 mg by Superior Source interact with any medications?
Yes. Based on its ingredients, B-1 100 mg has a known interaction with 262 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
B-1 100 mg contains 2 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is 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.
Is thiamine safe to take while I'm pregnant or breastfeeding?
Thiamine is actually needed in pregnancy and while breastfeeding. The safety data rates it as likely safe. Use only at the recommended dose and let your provider know you're taking a supplement so they can make sure it fits your plan.
What is thiamine, and what does it do in my body?
Thiamine is vitamin B-1, an essential nutrient that helps your body turn food into energy and keeps your nerves working properly. Your body can't make it, so you have to get it from food or supplements.
Does this product actually work for diabetes or blood pressure?
We don't have enough reliable evidence to say that stevia in this product works for those conditions. Some studies hint it might help with blood sugar, but others don't confirm it, and there's no solid proof for blood pressure.
What are the side effects of this supplement?
Thiamine is very well tolerated and serious side effects are rare. Stevia may cause bloating, dizziness, headache, muscle pain, nausea, or numbness, but those usually go away after the first week. Allergic reactions are uncommon.
Why does this tablet contain stevia if I'm just buying it for thiamine?
Stevia is a sweetener used to flavor the tablet without adding sugar. If you prefer a thiamine supplement without stevia, we can help you find another option.

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

Not sure if B-1 100 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.

B-1 100 mg label
Go deeper

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.

Herb & supplement monograph

Thiamine

Interacts with 3 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 enough from food, but supplements are clear...

Read the full Thiamine monograph → Herb & supplement monograph

Stevia

Interacts with 259 drugs

Stevia is a plant-based, calorie-free sweetener that is widely used as a sugar alternative and is considered safe in normal food amounts by major regulators. Purified stevia extracts have a...

Read the full Stevia monograph →
Sources

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.

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 17 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
  1. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
  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. 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
  4. 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
  5. 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
  6. Thiamine hydrochloride injection package insert. Lake Zurich, IL: Fresenius Kabi, LLC; September 2019.
  7. 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.

See these in context on the Thiamine monograph →

Stevia 10 references
  1. Chan P, Xu DY, Liu JC, et al. The effect of stevioside on blood pressure and plasma catecholamines in spontaneously hypertensive rats. Life Sci 1998;63:1679-84. PubMed
  2. Melis MS. A crude extract of Stevia rebaudiana increases the renal plasma flow of normal and hypertensive rats. Braz J Med Biol Res 1996;29:669-75.
  3. Melis MS. Chronic administration of aqueous extract of Stevia rebaudiana in rats: renal effects. J Ethnopharmacol 1995;47:129-34. PubMed
  4. Melis MS, Sainati AR. Effect of calcium and verapamil on renal function of rats during treatment with stevioside. J Ethnopharmacol 1991;33:257-622. PubMed
  5. Hsieh MH, Chan P, Sue YM, et al. Efficacy and tolerability of oral stevioside in patients with mild essential hypertension: a two-year, randomized, placebo-controlled study. Clin Ther 2003;25:2797-808. PubMed
  6. Chan P, Tomlinson B, Chen YJ, et al. A double-blind placebo-controlled study of the effectiveness and tolerability of oral stevioside in human hypertension. Br J Clin Pharmacol 2000;50:215-20. PubMed
  7. Gregersen S, Jeppesen PB, Holst JJ, Hermansen K. Antihyperglycemic effects of stevioside in type 2 diabetic subjects. Metabolism 2004;53:73-6. PubMed
  8. Barriocanal LA, Palacios M, Benitez G, et al. Apparent lack of pharmacological effect of steviol glycosides used as sweeteners in humans. A pilot study of repeated exposures in some normotensive and hypotensive individuals and in Type 1 and Type 2 diabeti
  9. Ferri LA, Alves-Do-Prado W, Yamada SS, et al. Investigation of the antihypertensive effect of oral crude stevioside in patients with mild essential hypertension. Phytother Res 2006;20:732-6. PubMed
  10. Almiron-Roig E, Navas-Carretero S, Castelnuovo G, et al. Impact of acute consumption of beverages containing plant-based or alternative sweetener blends on postprandial appetite, food intake, metabolism, and gastro-intestinal symptoms: Results of the SWEE

See these in context on the Stevia 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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