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Dietary supplement

Brewer's Yeast Ingredients & Drug Interactions

by Pure Herbs

Brewer's Yeast label
See full label image
Liquid Category: Botanical
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 9, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Brewer's Yeast 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: Major

Brewer's Yeast is a dietary supplement by Pure Herbs with 1 active ingredient. Its ingredients are commonly taken for source of b vitamins, diarrhea (certain types), cold and flu support.Based on those ingredients, 136 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Brewer's Yeast Extract. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Brewer's Yeast by Pure Herbs

Ask about any prescription or over-the-counter medication and we check it for interactions with Brewer's Yeast by Pure Herbs — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Brewer's Yeast by Pure Herbs

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 16, 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.

Pure Herbs Brewer's Yeast Extract is a single-ingredient liquid supplement containing brewer's yeast. That's it—no fillers or other inactive ingredients are listed.

Brewer's yeast is a byproduct of beer brewing that's rich in B vitamins, minerals, and protein, and it's been used traditionally to support digestive health and overall wellness.

Does it work?

Moderate 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

This product doesn't appear to be marketed for a specific use, so we graded Brewer's Yeast's overall clinical evidence instead.

Moderate

Some clinical evidence supports Brewer's Yeast for:

Why this rating?
  • The label markets general wellness (“energy and digestive health”), not a specific health condition, so there is no single claim to grade against clinical-evidence data.
  • Since the label doesn't commit to one use, we graded the ingredient's overall clinical evidence instead.
  • On file: Irritable bowel syndrome (IBS) — rated "Possibly Effective" (Natural Medicines).

The evidence is strongest for irritable bowel syndrome (IBS), where brewer's yeast is rated possibly effective. For other uses listed in our data—Clostridioides difficile infection, influenza, high cholesterol, and hay fever—there isn't enough reliable evidence yet to say whether it works.

If you're considering this for one of those conditions, talk it over with your doctor or pharmacist about whether the current evidence supports a trial.

The evidence, ingredient by ingredient Brewer's Yeast

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.

Brewer's yeast is generally well tolerated in food amounts, but concentrated supplements are less studied. The most common side effects are gas and migraines—something to expect, especially at first.

Rarely, it can cause serious reactions like fungemia (yeast entering the bloodstream) or anaphylaxis in sensitive people, and it may not be safe for those with weakened immune systems. During pregnancy and breastfeeding, food amounts are likely fine, but the safety of supplement doses isn't well established—check with your doctor or pharmacist before taking it.

Side effects, ingredient by ingredient Brewer's Yeast

Meds to double-check

Major interaction found
Known Interaction Concern · database check
Major identified

At least one ingredient has a documented Major-severity interaction. Check your medications for a personalized result.

Why this rating?
  • 1 of the 1 matched ingredient can interact with medications — Brewer's Yeast.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: diabetes medications; lithium.
  • For scale: 136 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.

Stop and check with your doctor or pharmacist before using this product if you take a monoamine oxidase inhibitor (MAOI) antidepressant—the risk of a dangerous blood pressure spike is serious. Also check first if you take diabetes medications, lithium, or antifungals.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with some supporting evidence behind its ingredients' uses. Major medication interactions have been identified, and safety information is well characterized.

Brewer's yeast may help with IBS, but it's not right for everyone. If you take an MAOI antidepressant, diabetes medication, lithium, or antifungals, you need to check with your doctor or pharmacist first.

Even in people without those medications, gas and headaches are common. Have a conversation with your healthcare provider before starting—they know your full picture.

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 Dec 13, 2022.

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 Brewer's Yeast, straight from the product label.

Brand Pure Herbs
Net contents 1 Fluid Ounce(s); 30 mL
Market status On market
Date entered into DSLD Dec 13, 2022
DSLD ID 278750
Product type Botanical
Supplement form Liquid
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Women (not pregnant or lactating)
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 Brewer's Yeast by Pure Herbs, 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:
2 mL
Maximum serving Sizes:
2 mL
Servings per container
15
IngredientAmount% DV
Brewer's Yeast Extract2024 mg--

Other ingredients: None

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.
Suggested/Recommended/Usage/Directions

Directions: For adults, mix 2 mL (abt. 1/2 tsp) of extract in 2 fl. oz (60 mL) water one time daily preferably with a meal.

Shake well before use

Formulation

Beneficial for energy and digestive health.

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.

Precautions

Warning: Not intended for use by pregnant or nursing women. If you have a medical condition or are taking medication, consult your doctor prior to use.

Discontinue use and consult with your doctor if any adverse reactions occur.

Keep out of reach of children

Contains: Gluten

Brand IP Statement(s)

Pure Herbs, Ltd. Natural Herbal Extracts

FDA Statement of Identity

Dietary Supplement

General Statements

"No expense has been spared to provide the finest nature has to offer."

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

See for yourself

Brewer's Yeast by Pure Herbs label

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

Brewer's Yeast 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 Brewer's Yeast by Pure Herbs

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

Serving size2 mL Dosage formLiquid Servings per container15 Amounts shown are per serving.

Brewer's Yeast Extract

Interacts with
136 drugs
2024 mg per serving Form: Saccharomyces sp. Extract

Brewer's yeast is a nutrient-rich fungus that provides B vitamins, protein, and minerals, and a related yeast product (S. boulardii) is used for some...

Brewer's Yeast Extract monograph & interactions

Other (inactive) ingredients: None. These complete the product’s ingredient list but are not active constituents.

Interaction report

Brewer's Yeast by Pure Herbs Drug Interactions

Want to check YOUR meds against Brewer's Yeast?

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
136Drugs
9 Major 87 Moderate 40 Minor

Ingredients driving the most interactions

Brewer's Yeast Extract 136

Individual Drug Interactions

The ingredients in Brewer's Yeast interact with 136 drugs. Click any drug to see the details.

1 of the 1 ingredient in Brewer's Yeast interact with drugs. Each result below shows which ingredient is responsible. Brewer's Yeast Extract

Each ingredient & the kinds of drugs it affects

For each ingredient in Brewer's Yeast 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.

Brewer's Yeast Extract4 drug types · 136 drugs

Monoamine Oxidase Inhibitors (Maois)

Theoretically, taking brewer's yeast with MAOIs might increase the risk of hypertension.
Brewer's yeast contains tyramine. Taking brewer's yeast with MAOIs might increase the risk for hypertensive crisis.

Likelihood Likely Evidence D
Antidiabetes Drugs

Taking brewer's yeast with antidiabetes drugs might increase the risk of hypoglycemia.
Clinical research shows that taking chromium-containing brewer's yeast can decrease levels of blood glucose in diabetic patients being treated with antidiabetes drugs.

Likelihood Possible Evidence B
Lithium

Theoretically, taking brewer's yeast with lithium might cause additive effects and side effects.
Some brewer's yeast products contains lithium.

Likelihood Possible Evidence D
Antifungals

Theoretically, taking antifungals with some brewer's yeast products might decrease the effectiveness of brewer's yeast.
Some brewer's yeast products contain live yeast. Therefore, simultaneously taking antifungals might kill a significant number of the organisms.

Likelihood Possible Evidence D
Brewer's Yeast Extract full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Brewer's Yeast, from the product label.

Pure Herbs

See all Pure Herbs products
Name
Pure Herbs, Ltd.
City
Sterling Heights
State
MI
Phone Number
(800) 860-4372
Web Address
www.pureherbs.com
Pharmacist Counseling Corner

Brewer's Yeast by Pure Herbs: Common Questions

Does Brewer's Yeast by Pure Herbs interact with any medications?
Yes. Based on its ingredients, Brewer's Yeast has a known interaction with 136 medications, including 9 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Brewer's Yeast 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 brewer's yeast lower my blood sugar if I'm on diabetes medication?
Brewer's yeast can lower blood glucose levels, so when taken with antidiabetes drugs, there's a moderate risk of blood sugar dropping too low (hypoglycemia). Your doctor or pharmacist needs to know you're considering this before you start.
What are the most common side effects I might feel?
Gas and migraines are the side effects most people notice, especially when they first start. Intestinal discomfort and anal irritation have been reported rarely. Most people tolerate it well in the short term.
Is brewer's yeast safe during pregnancy?
Food amounts are likely fine, but the safety of concentrated supplement doses during pregnancy hasn't been well studied. Talk with your doctor or pharmacist to decide what's right for you.
Can brewer's yeast help with IBS?
Brewer's yeast is rated possibly effective for irritable bowel syndrome. For other conditions like hay fever, high cholesterol, or influenza, we don't have enough reliable evidence yet to say whether it works.
Is it safe for people with weakened immune systems?
Brewer's yeast may not be safe for people with weakened immune systems. Check with your doctor or pharmacist to see if this product is appropriate for your situation.

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

Not sure if Brewer's Yeast is safe with your meds?

Our pharmacists answer your medication & supplement questions — free.

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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.

Brewer's Yeast label
Go deeper

The Full Monographs Behind Brewer's Yeast’s Ingredients

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

Herb & supplement monograph

Brewer's Yeast

Interacts with 136 drugs

Brewer's yeast is a nutrient-rich fungus that provides B vitamins, protein, and minerals, and a related yeast product (S. boulardii) is used for some types of diarrhea. Most other health cla...

Read the full Brewer's Yeast monograph →
Sources

Sources & How We Checked

Brewer's Yeast'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 6 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.

Brewer's Yeast 6 references
  1. Blumenthal M, ed. The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. Trans. S. Klein. Boston, MA: American Botanical Council, 1998.
  2. Lewis SJ, Freedman AR. Review article: the use of biotherapeutic agents in the prevention and treatment of gastrointestinal disease. Aliment Pharmacol Ther 1998;12:807-22. PubMed
  3. Bahijiri, S. M., Mira, S. A., Mufti, A. M., and Ajabnoor, M. A. The effects of inorganic chromium and brewer's yeast supplementation on glucose tolerance, serum lipids and drug dosage in individuals with type 2 diabetes. Saudi.Med.J. 2000;21(9):831-837. DOI
  4. Schrauzer, G. N. and de, Vroey E. Effects of nutritional lithium supplementation on mood. A placebo-controlled study with former drug users. Biol.Trace Elem.Res. 1994;40(1):89-101. PubMed
  5. Gayathri R, Aruna T, Malar S, Shilpa B, Dhanasekar KR. Efficacy of Saccharomyces cerevisiae CNCM I-3856 as an add-on therapy for irritable bowel syndrome. Int J Colorectal Dis. 2020;35(1):139-145. PubMed
  6. Mourey F, Decherf A, Jeanne JF, et al. Saccharomyces cerevisiae I-3856 in irritable bowel syndrome with predominant constipation. World J Gastroenterol 2022;28(22):2509-2522.

See these in context on the Brewer's Yeast 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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