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Dietary supplement

Saccharomyces Boulardii Ingredients & Drug Interactions

by NOW

Saccharomyces Boulardii label
See full label image
Capsule Category: Non-nutrient/non-botanical
Most serious interaction: Minor
Clinical methodology reviewed by · Updated Sep 30, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Saccharomyces Boulardii 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: Minor

Saccharomyces Boulardii is a dietary supplement by NOW with 1 active ingredient. Its ingredients are commonly taken for acute diarrhea, antibiotic-associated diarrhea, traveler's diarrhea.Based on those ingredients, 40 medications have a known interaction with it, the most serious rated minor. The ingredients most likely to interact are Saccharomyces boulardii. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Saccharomyces Boulardii by NOW

Ask about any prescription or over-the-counter medication and we check it for interactions with Saccharomyces Boulardii by NOW — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Saccharomyces Boulardii by NOW

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 Oct 1, 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: Saccharomyces boulardii, a beneficial yeast strain used to support digestive health. It also includes three inactive ingredients — hypromellose (a capsule binder), inulin (a prebiotic fiber), and guar gum (a thickener) — which are excipients that have no active role in the supplement.

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
Moderate

Some clinical evidence supports this product's ingredients for its stated purpose, but it isn't conclusive.

Why this rating?
  • The label markets this product for: promotes intestinal tract and gut flora health.
  • We looked for evidence on: Antibiotic-associated diarrhea, Travelers' diarrhea, Clostridioides difficile infection, Rotaviral diarrhea, Irritable bowel syndrome (IBS), Crohn disease — and 4 related terms.
  • The strongest evidence on file: Saccharomyces Boulardii is rated "Possibly Effective" for Antibiotic-associated diarrhea (Natural Medicines).
  • Also on file: Saccharomyces Boulardii is rated "Possibly Effective" for Helicobacter pylori, Rotaviral diarrhea, Travelers' diarrhea, Clostridioides difficile infection.
  • Also on file: Saccharomyces Boulardii is rated "Insufficient Reliable Evidence To Rate" for Constipation, Crohn disease.

The evidence for Saccharomyces boulardii is rated as possibly effective for several digestive issues: rotaviral diarrhea, travelers' diarrhea, antibiotic-associated diarrhea, necrotizing enterocolitis (a serious intestinal condition in newborns), Clostridioides difficile infection (a bacterial infection that causes severe diarrhea), and Helicobacter pylori infection. 'Possibly effective' means there's some support from research, but more robust evidence would strengthen confidence. The data we hold doesn't detail how strong that evidence is for each condition.

The evidence, ingredient by ingredient Saccharomyces Boulardii

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.

Saccharomyces boulardii is generally well tolerated in healthy adults, but it should be avoided by people who are critically ill or immunocompromised (have weak immune systems), because rare but serious yeast infections of the bloodstream (fungemia) have been reported in those populations — especially in ICU patients with central catheters, those on feeding tubes, or those on broad-spectrum antibiotics. Gastrointestinal side effects are also rare and may include abdominal cramps, bloating, nausea, vomiting, or loss of appetite.

Because overall safety data is limited, speak with your doctor before starting this supplement.

Side effects, ingredient by ingredient Saccharomyces Boulardii

Meds to double-check

Minor interactions only
Known Interaction Concern · database check
Minor only

Only Minor-severity interactions are documented for these ingredients.

Why this rating?
  • 1 of the 1 matched ingredient can interact with medications — Saccharomyces Boulardii.
  • The most serious interaction on file is rated Minor.
  • For scale: 40 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 any antifungal medication (oral, topical, or for systemic fungal infections), double-check with your doctor or pharmacist before adding this supplement, because antifungals may reduce how well the probiotic works. Additionally, if you're critically ill, immunocompromised, on broad-spectrum antibiotics, or have a central venous catheter or feeding tube, talk with your doctor before use — the risk of serious yeast infection is higher in those situations.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with some supporting evidence for its stated purpose. Only minor medication interactions are documented, and safety information is well characterized.

This probiotic may help with several types of diarrhea and digestive infections, but it's not for everyone. If you're critically ill or have a weakened immune system, you should avoid it.

Check with your doctor or pharmacist before starting — especially if you take antifungal medications, and especially if you have health conditions that put you at higher risk.

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 Jul 25, 2024.

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 Saccharomyces Boulardii, straight from the product label.

Brand NOW
Barcode (UPC) 733739029348
Net contents 60 Veg Capsule(s)
Market status On market
Date entered into DSLD Jul 25, 2024
DSLD ID 314062
Product type Non-nutrient/non-botanical
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Vegan, Vegetarian, Adult (18 - 50 Years), Kosher, Halal, Gluten 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 Saccharomyces Boulardii by NOW, 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 Veg Capsule(s)
Maximum serving Sizes:
2 Veg Capsule(s)
Servings per container
30
UPC/BARCODE
733739029348
IngredientAmount% DV
Saccharomyces boulardii1000 mg--

Other ingredients: Hypromellose, Inulin, Guar Gum

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

Suggested Usage: Take 1-2 capsules 2 to 3 times daily between meals as needed.

Storage

Refrigerate to maintain potency.

Formula

Saccharomyces boulardii is a probiotic yeast that survives stomach acid and colonizes the intestinal tract. It promotes the health of the intestinal tract, helps to encourage a healthy gut flora balance, and supports a balanced intestinal response to normal internal and environmental stressors. Saccharomyces boulardii has also been shown to support proper gastrointestinal function during temporary disruptions to the normal balance of gut flora.

Probiotic - 5 billion CFU

Triangle K (Kosher)

Crescent H (Halal)

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.

Precautions

Caution: Consult physician if pregnant/nursing, taking medication (especially immune-suppressing drugs), or have a medical condition (especially if immune system is compromised).

Keep out of reach of children.

Not manufactured with wheat, gluten, soy, corn, milk, egg, fish, shellfish, tree nut or sesame ingredients. Produced in a GMP facility that processes other ingredients containing these allergens.

General Statements

This bottle is made from 100% PCR (post-consumer recycled) resin.

Digestive Family owned since 1968.

Formulation

For occasional diarrhea Supports a healthy balance of intestinal flora Useful when traveling

Gluten-Free

Non-GMO

Vegetarian/Vegan

Made and quality tested in the USA with globally sourced ingredients.

Not manufactured with wheat, gluten, soy, corn, milk, egg, fish, shellfish, tree nut or sesame ingredients.

Natural color variation may occur in this product.

FDA Statement of Identity

A Dietary Supplement

Seals/Symbols

Triangle K (Kosher)

GMP Quality Assured

Crescent H (Halal)

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

See for yourself

Saccharomyces Boulardii by NOW label

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

Saccharomyces Boulardii 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 Saccharomyces Boulardii by NOW

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

Serving size1 Veg Capsule(s) Dosage formCapsule Servings per container30 Amounts shown are per serving.

Saccharomyces boulardii

Interacts with
40 drugs
1000 mg per serving Form: Saccharomyces cerevisiae var. boulardii I-3799

Saccharomyces boulardii is a beneficial yeast used as a probiotic, with the strongest evidence for preventing and treating certain types of diarrhea,...

Saccharomyces boulardii monograph & interactions

Other (inactive) ingredients: Hypromellose, Inulin, Guar Gum. These complete the product’s ingredient list but are not active constituents.

Interaction report

Saccharomyces Boulardii by NOW Drug Interactions

Want to check YOUR meds against Saccharomyces Boulardii?

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
40Drugs
40 Minor

Ingredients driving the most interactions

Saccharomyces boulardii 40

Individual Drug Interactions

The ingredients in Saccharomyces Boulardii interact with 40 drugs. Click any drug to see the details.

1 of the 1 ingredient in Saccharomyces Boulardii interact with drugs. Each result below shows which ingredient is responsible. Saccharomyces boulardii

Each ingredient & the kinds of drugs it affects

For each ingredient in Saccharomyces Boulardii 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.

Saccharomyces boulardii1 drug type · 40 drugs

Antifungals

Theoretically, taking antifungals with Saccharomyces boulardii might decrease the effectiveness of Saccharomyces boulardii.
S. boulardii is a live yeast. Therefore, simultaneously taking antifungals might kill a significant number of the organisms.

Likelihood Possible Evidence D
Saccharomyces boulardii full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Saccharomyces Boulardii, from the product label.

NOW

See all NOW products
Name
NOW FOODS
Street Address
395 S. Glen Ellyn Rd.
City
Bloomingdale
State
IL
ZipCode
60108
Web Address
nowfoods.com
Pharmacist Counseling Corner

Saccharomyces Boulardii by NOW: Common Questions

Does Saccharomyces Boulardii by NOW interact with any medications?
Yes. Based on its ingredients, Saccharomyces Boulardii has a known interaction with 40 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Saccharomyces Boulardii 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 kill my antifungal medication or make it less effective?
No — the interaction works the other way. The antifungal may kill off the live yeast in this supplement, making the probiotic less effective. If you take an antifungal, check with your doctor about timing or whether to use them together at all.
Can I take this if I'm on antibiotics?
That depends on the antibiotic and your overall health. Saccharomyces boulardii is sometimes used to help prevent antibiotic-associated diarrhea, but people on broad-spectrum antibiotics — especially if they're critically ill — do face a higher risk of rare yeast infection. Talk with your doctor before starting it alongside antibiotics.
What are the common side effects?
Rare gastrointestinal complaints have been reported: abdominal cramps, bloating, nausea, vomiting, or decreased appetite. Serious yeast infection of the blood is also rare but has occurred in critically ill or immunocompromised patients, particularly those with central catheters or on feeding tubes.
Is there safety data for pregnancy and breastfeeding?
The data we hold doesn't include safety information for pregnancy or lactation. Talk with your doctor or midwife before use if you're pregnant or breastfeeding.
Who shouldn't take this?
You should avoid it if you're critically ill, have a weakened immune system, have a central venous catheter, are on a feeding tube, or are on broad-spectrum antibiotics — the risk of serious yeast infection is higher in those situations. Also skip it if you're taking antifungal medication without checking first.

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

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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.

Saccharomyces Boulardii label
Go deeper

The Full Monographs Behind Saccharomyces Boulardii’s Ingredients

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

Herb & supplement monograph

Saccharomyces Boulardii

Interacts with 40 drugs

Saccharomyces boulardii is a beneficial yeast used as a probiotic, with the strongest evidence for preventing and treating certain types of diarrhea, including antibiotic-associated diarrhea...

Read the full Saccharomyces Boulardii monograph →
Sources

Sources & How We Checked

Saccharomyces Boulardii'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 26 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.

Saccharomyces Boulardii 26 references
  1. Niault M, Thomas F, Prost J, et al. Fungemia due to Saccharomyces species in a patient treated with enteral Saccharomyces boulardii. Clin Infect Dis 1999;28:930.
  2. Pletinex M, Legein J, Vandenplas Y. Fungemia with Saccharomyces boulardii in a 1-year-old girl with protracted diarrhea. J Pediatr Gastroenterol Nutr 1995;21:113-5. DOI
  3. Fredenucci I, Chomarat M, Boucaud C, et al. Saccharomyces boulardii fungemia in a patient receiving ultra-levure therapy. Clin Infect Dis 1998;27:222-3.
  4. Elmer GW, McFarland LV, Surawicz CM, et al. Behaviour of Saccharomyces boulardii in recurrent Clostridium difficile disease patients. Aliment Pharmacol Ther 1999;13:1663-8.
  5. 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
  6. Cesaro S, Chinello P, Rossi L, Zanesco L. Saccharomyces cerevisiae fungemia in a neutropenic patient treated with Saccharomyces boulardii. Support Care Cancer 2000;8:504-5. PubMed
  7. Hennequin C, Thierry A, Richard GF, et al. Microsatellite typing as a new tool for identification of Saccharomyces cerevisiae strains. J Clin Microbiol 2001;39:551-9.
  8. Plein K, Hotz J. Therapeutic effects of Saccharomyces boulardii on mild residual symptoms in a stable phase of Crohn's disease with special respect to chronic diarrhea - a pilot study. Z Gastroenterol 1993;31:129-34.
  9. Borriello SP, Hammes WP, Holzapfel W, et al. Safety of probiotics that contain lactobacilli or bifidobacteria. Clin Infect Dis 2003;36:775-80. PubMed
  10. Marteau P, Seksik P. Tolerance of probiotics and prebiotics. J Clin Gastroenterol 2004;38:S67-9. PubMed
  11. Munoz P, Bouza E, Cuenca-Estrella M, et al. Saccharomyces cerevisiae fungemia: an emerging infectious disease. Clin Infect Dis 2005;40:1625-34. PubMed
  12. Lherm, T., Monet, C., Nougiere, B., Soulier, M., Larbi, D., Le Gall, C., Caen, D., and Malbrunot, C. Seven cases of fungemia with Saccharomyces boulardii in critically ill patients. Intensive Care Med 2002;28(6):797-801. PubMed
  13. Riquelme, A. J., Calvo, M. A., Guzman, A. M., Depix, M. S., Garcia, P., Perez, C., Arrese, M., and Labarca, J. A. Saccharomyces cerevisiae fungemia after Saccharomyces boulardii treatment in immunocompromised patients. J Clin.Gastroenterol. 2003;36(1):41- PubMed
  14. Cherifi, S., Robberecht, J., and Miendje, Y. Saccharomyces cerevisiae fungemia in an elderly patient with Clostridium difficile colitis. Acta Clin Belg. 2004;59(4):223-224. PubMed
  15. Ellouze O, Berthoud V, Mervant M, Parthiot JP, Girard C. Septic shock due to Sacccaromyces boulardii. Med Mal Infect. 2016;46(2):104-105.
  16. Appel-da-Silva MC, Narvaez GA, Perez LRR, Drehmer L, Lewgoy J. Saccharomyces cerevisiae var. boulardii fungemia following probiotic treatment. Med Mycol Case Rep. 2017;18:15-7. PubMed
  17. Atici S, Soysal A, Karadeniz Cerit K, et al. Catheter-related Saccharomyces cerevisiae Fungemia Following Saccharomyces boulardii Probiotic Treatment: In a child in intensive care unit and review of the literature. Med Mycol Case Rep. 2017;15:33-35. PubMed
  18. Martin IW, Tonner R, Trivedi J, et al. Saccharomyces boulardii probiotic-associated fungemia: questioning the safety of this preventive probiotic's use. Diagn Microbiol Infect Dis. 2017;87(3):286-8. PubMed
  19. Romanio MR, Coraine LA, Maielo VP, Abramczyc ML, Souza RL, Oliveira NF. Saccharomyces cerevisiae fungemia in a pediatric patient after treatment with probiotics. Rev Paul Pediatr 2017;35(3):361-4.
  20. Roy U, Jessani LG, Rudramurthy SM, et al. Seven cases of Saccharomyces fungaemia related to use of probiotics. Mycoses 2017;60(6):375-380.
  21. Romanio MR, Coraine LA, Maielo VP, Abramczyc ML, Souza RL, Oliveira NF. Saccharomyces cerevisiae fungemia in a pediatric patient after treatment with probiotics. Rev Paul Pediatr. 2017 Jul-Sep;35(3):361-364. doi: 10.1590/1984-0462/;2017;35;3;00014.
  22. Flatley EA, Wilde AM, Nailor MD. Saccharomyces boulardii for the prevention of hospital onset Clostridium difficile infection. J Gastrointestin Liver Dis. 2015;24(1):21-4. PubMed
  23. Ventoulis I, Sarmourli T, Amoiridou P, et al. Bloodstream infection by Saccharomyces cerevisiae in two COVID-19 patients after receiving supplementation of Saccharomyces in the ICU. J Fungi (Basel). 2020;6(3):98. PubMed
  24. Wombwell E, Bransteitter B, Gillen LR. Incidence of Saccharomyces cerevisiae fungemia in hospitalised patients administered Saccharomyces boulardii probiotic. Mycoses 2021;64(12):1521-1526.
  25. Rannikko J, Holmberg V, Karppelin M, et al. Fungemia and Other Fungal Infections Associated with Use of Saccharomyces boulardii Probiotic Supplements. Emerg Infect Dis 2021;27(8):2090-6.
  26. Awoyemi A, Mayerhofer C, Felix AS, et al. Rifaximin or Saccharomyces boulardii in heart failure with reduced ejection fraction: Results from the randomized GutHeart trial. EBioMedicine 2021;70:103511. PubMed

See these in context on the Saccharomyces Boulardii 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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