Interactions on record — worth a quick check against your medications. Based on 3 of 4 ingredients. Check your meds →
Dietary supplement

Acidophilus Probiotic Blend Ingredients & Drug Interactions

by 21st Century

Capsule Category: Non-nutrient/non-botanical
Most serious interaction: Moderate
The interaction bottom line Most serious interaction: Moderate

Acidophilus Probiotic Blend is a dietary supplement by 21st Century with 4 active ingredients. Its ingredients are commonly taken for digestive health and balance, diarrhea (including antibiotic-related), vaginal yeast and bacterial infections.Based on those ingredients, 182 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Lactobacillus acidophilus, Bifidobacterium bifidum. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

HelloPharmacist Scorecard of Acidophilus Probiotic Blend by 21st Century

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

What’s inside

Low disclosure
Ingredient Transparency · database check
Low

Most active ingredients don't disclose an individual amount — you can't tell how much of each you're getting.

Why this rating?
  • The label discloses an exact amount for 0 of its 4 active ingredients.
  • “Proprietary Blend” is a proprietary blend — the label gives one combined amount (175 mg) without saying how much of each component you get.

This blend contains 4 active ingredients, all live probiotic bacteria: Lactobacillus acidophilus, Lactobacillus salivarius, Bifidobacterium bifidum, and Streptococcus thermophilus. These are 'good' bacteria meant to support digestive health.

The inactive ingredients include whey, inulin, gelatin, cellulose, citrus pectin, and less than 2% of other materials.

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: aid in the maintenance of digestive health.
  • We looked for evidence on: Antibiotic-associated diarrhea, Bacterial vaginosis, Clostridioides difficile infection, Colic, Constipation, Diarrhea — and 4 related terms.
  • The strongest evidence on file: Lactobacillus Acidophilus is rated "Possibly Effective" for Antibiotic-associated diarrhea (Natural Medicines).
  • Also on file: Lactobacillus Acidophilus is rated "Possibly Effective" for Bacterial vaginosis, Irritable bowel syndrome (IBS).
  • Also on file: Bifidobacterium Bifidum is rated "Possibly Effective" for Irritable bowel syndrome (IBS).

The evidence is mixed here. Lactobacillus acidophilus is possibly effective for irritable bowel syndrome (IBS), antibiotic-associated diarrhea, Helicobacter pylori infection, and bacterial vaginosis.

Bifidobacterium bifidum is possibly effective for IBS and respiratory tract infections. Streptococcus thermophilus has insufficient evidence in our data for any of the conditions studied — we don't know yet if it works for antibiotic-associated diarrhea, bacterial vaginosis, constipation, diabetes, or other uses.

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 3 of the 3 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 3 of 3.
  • General safety write-ups exist for 3 of 3.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Lactobacillus acidophilus and Bifidobacterium bifidum are generally well tolerated in healthy adults and children. The main caution: since these are live organisms, there's a small theoretical risk of infection in people with severely weakened immune systems, though this is rare.

Uncommon gastrointestinal side effects like bloating, flatulence, abdominal pain, and diarrhea have been reported with probiotic blends. Streptococcus thermophilus is also generally well tolerated, though people with compromised immune systems should check with their doctor first.

All three ingredients carry a 'possibly safe' rating in pregnancy, but the data are limited — talk with your doctor or pharmacist if you're pregnant or nursing.

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 3 matched ingredients can interact with medications — Lactobacillus Acidophilus, Bifidobacterium Bifidum.
  • The most serious interaction on file is rated Moderate.
  • For scale: 182 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 antibiotic drugs, tell your pharmacist — timing between antibiotics and this probiotic matters. That's the main medication interaction documented for these ingredients.

Check your full medication list with the tool on this page.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFormula with limited ingredient disclosure with some supporting evidence for its stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

This probiotic blend may help with IBS, antibiotic-associated diarrhea, or certain infections, though evidence is stronger for some uses than others. If you're on antibiotics, space out when you take this — the antibiotic can kill the beneficial bacteria.

Anyone with a weakened immune system should check with their doctor first. Ask your pharmacist to review your medications before you start.

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

Assessment coverage: 3 of 4 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Oct 23, 2019.

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 Acidophilus Probiotic Blend, straight from the product label.

Brand 21st Century
Barcode (UPC) 740985229286
Net contents 150 Capsule(s)
Market status On market
Date entered into DSLD Oct 23, 2019
DSLD ID 206609
Product type Non-nutrient/non-botanical
Supplement form Capsule
Dietary claims / uses Nutrient, All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), 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 Acidophilus Probiotic Blend by 21st Century, 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 Capsule(s)
Maximum serving Sizes:
1 Capsule(s)
UPC/BARCODE
740985229286
IngredientAmount% DV
Proprietary Blend175 mg--
Lactobacillus acidophilus0 NP--
Lactobacillus salivarius0 NP--
Bifidobacterium bifidum0 NP--
Streptococcus thermophilus0 NP--

Other ingredients: Whey, Inulin, Gelatin, Cellulose, Citrus Pectin, Contains <2% of

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.
Formula

A proprietary blend of the most beneficial known strain of Lactobacillus acidophilus, synergistically combined with three other genetically distinct probiotic organisms and the prebioitc Inulin, is designed to aid in the maintenance of probiotic activity in the intestine.

Contains milk ingredients (whey).

Suggested/Recommended/Usage/Directions

Directions: As a dietary supplement, adults take one (1) capsule daily with any meal or as directed by a healthcare provider. Do not exceed recommended dosage.

Precautions

Do not exceed recommended dosage.

Warning: Consult a healthcare provider prior to use if pregnant, nursing, on medications, have a medical condition or are planning a medical procedure.

Stop use and contact a physician if adverse reactions occur.

Keep out of reach of children.

Do not use if product appears to be tampered with or seal is broken.

Contains milk ingredients (whey).

General Statements

Individual results may vary.

Proprietary Blend Designed to Support Healthy Intestinal Flora

Storage

Store at room temperature.

Formulation

No added Sugar, Salt, Preservatives, Artificial Flavors or Colors. Gluten Free.

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.

FDA Statement of Identity

Dietary Supplement

Seals/Symbols

Gluten free

Guaranteed quality Laboratory tested

See for yourself

Acidophilus Probiotic Blend by 21st Century label

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

What’s inside

The Ingredients in Acidophilus Probiotic Blend by 21st Century

These are the 4 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 Capsule(s) Dosage formCapsule 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.

Proprietary Blend

175 mg per serving

Other (inactive) ingredients: Whey, Inulin, Gelatin, Cellulose, Citrus Pectin, Contains <2% of. These complete the product’s ingredient list but are not active constituents.

Interaction report

Acidophilus Probiotic Blend by 21st Century Drug Interactions

Want to check YOUR meds against Acidophilus Probiotic Blend?

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
182Drugs
182 Moderate

Ingredients driving the most interactions

Each ingredient & the kinds of drugs it affects

For each ingredient in Acidophilus Probiotic Blend 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.

Lactobacillus acidophilus1 drug type · 182 drugs

Antibiotic Drugs

Theoretically, taking Lactobacillus acidophilus with antibiotic drugs might decrease the effectiveness of L. acidophilus.
L. acidophilus preparations usually contain live and active organisms. Therefore, simultaneously taking antibiotics might kill a significant number of the organisms. Tell patients to separate administration of antibiotics and L. acidophilus preparations by at least two hours.

Likelihood Probable Evidence D

Bifidobacterium bifidum1 drug type · 182 drugs

Antibiotic Drugs

Theoretically, taking Bifidobacterium. bifidum with antibiotic drugs might decrease the effectiveness of B. bifidum.
Since B. bifidum preparations usually contain live and active organisms, simultaneously taking antibiotics might kill a significant number of the organisms. Tell patients to separate administration of antibiotics and B. bifidum preparations by at least 2 hours.

Likelihood Probable Evidence D
The maker

Brand information

Manufacturer and brand details for Acidophilus Probiotic Blend, from the product label.

21st Century

See all 21st Century products
Name
21st Century HealthCare, Inc.
Street Address
2119 S. Wilson St.
City
Tempe
State
AZ
ZipCode
85282
Web Address
www.21stcenturyvitamins.com
Pharmacist Counseling Corner

Acidophilus Probiotic Blend by 21st Century: Common Questions

Does Acidophilus Probiotic Blend by 21st Century interact with any medications?
Yes. Based on its ingredients, Acidophilus Probiotic Blend has a known interaction with 182 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Acidophilus Probiotic Blend contains 4 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.
Can I take this while I'm on antibiotics?
Not at the same time. Antibiotics can kill the live bacteria in this probiotic, making it less effective. Your pharmacist can help you space them out properly — usually a few hours apart works well.
Is this safe if I have a weakened immune system?
These are live organisms, so there's a caution for people with severely compromised immunity — though serious infection is rare. Talk with your doctor before starting if your immune system is weakened.
Will this help with IBS?
Lactobacillus acidophilus and Bifidobacterium bifidum are both possibly effective for IBS based on the evidence we have, but results vary from person to person.
What side effects might I get?
Uncommon ones include bloating, flatulence, abdominal discomfort, and diarrhea. Most people tolerate this blend well, but if you notice new symptoms, mention them to your pharmacist.
Is it safe to take during pregnancy?
The ingredients here carry a 'possibly safe' rating in pregnancy, but the data are limited. Check with your doctor or pharmacist for personalized advice — they know your full health picture.

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

Not sure if Acidophilus Probiotic Blend is safe with your meds?

Our pharmacists answer your medication & supplement questions — free.

Ask a pharmacist

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.

Acidophilus Probiotic Blend label
Sources

Sources & How We Checked

Acidophilus Probiotic Blend'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 43 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.

Lactobacillus Acidophilus 15 references
  1. Pierce A. The American Pharmaceutical Association Practical Guide to Natural Medicines. New York: The Stonesong Press, 1999:19.
  2. Begtrup LM, de Muckadell OB, Kjeldsen J, Christensen RD, Jarbøl DE. Long-term treatment with probiotics in primary care patients with irritable bowel syndrome--a randomised, double-blind, placebo controlled trial. Scand J Gastroenterol 2013;48(10):1127-35 PubMed
  3. Chatterjee S, Kar P, Das T, Ray S, Gangulyt S, Rajendiran C, Mitra M. Randomised placebo-controlled double blind multicentric trial on efficacy and safety of Lactobacillus acidophilus LA-5 and Bifidobacterium BB-12 for prevention of antibiotic-associated
  4. Shavakhi A, Tabesh E, Yaghoutkar A, Hashemi H, Tabesh F, Khodadoostan M,Minakari M, Shavakhi S, Gholamrezaei A. The effects of multistrain probiotic compound on bismuth-containing quadruple therapy for Helicobacter pylori infection: a randomized placebo-c
  5. Karamali M, Dadkhah F, Sadrkhanlou M, et al. Effects of probiotic supplementation on glycaemic control and lipid profiles in gestational diabetes: a randomized, double-blind, placebo-controlled trial. Diabetes Metab 2016;42(4):234-41. PubMed
  6. Badehnoosh B, Karamali M, Zarrati M, et al. The effects of probiotic supplementation on biomarkers of inflammation, oxidative stress and pregnancy outcomes in gestational diabetes. J Matern Fetal Neonatal Med. 2018 May;31(9):1128-1136.
  7. Kumar S, Kumar R, Rohilla L, Jacob N, Yadav J, Sachdeva N. A high potency multi-strain probiotic improves glycemic control in children with new-onset type 1 diabetes mellitus: A randomized, double-blind, and placebo-controlled pilot study. Pediatr Diabete
  8. Shahriari A, Karimi E, Shahriari M, Aslani N, Khooshideh M, Arab A. The effect of probiotic supplementation on the risk of gestational diabetes mellitus among high-risk pregnant women: A parallel double-blind, randomized, placebo-controlled clinical trial PubMed
  9. Xiao SD, Zhang DZ, Lu H, et al. Multicenter, randomized, controlled trial of heat-killed Lactobacillus acidophilus LB in patients with chronic diarrhea. Adv Ther. 2003;20(5):253-60.
  10. Rossi F, Amadoro C, Gasperi M, Colavita G. Lactobacilli infection case reports in the last three years and safety implications. Nutrients. 2022;14(6):1178. PubMed
  11. Ozer M, Goksu SY, Shahverdiani A, Mustafa M. Lactobacillus acidophilus-induced endocarditis and associated splenic abscess. Case Rep Infect Dis 2020;2020:1382709.
  12. Sadrin S, Sennoune S, Gout B, et al. A 2-strain mixture of Lactobacillus acidophilus in the treatment of irritable bowel syndrome: A placebo-controlled randomized clinical trial. Dig Liver Dis 2020;52(5):534-540. PubMed
  13. Stoffer JN, Slingsby TJ, Giuliari GP. Lactobacillus acidophilus endophthalmitis after intravitreal bevacizumab injection requiring intraocular lens explantation. Can J Ophthalmol 2022;57(1):e21-e22. PubMed
  14. Cukovic-Cavka S, Likic R, Francetic I, Rustemovic N, Opacic M, Vucelic B. Lactobacillus acidophilus as a cause of liver abscess in a NOD2/CARD15-positive patient with Crohn's disease. Digestion 2006;73(2-3):107-10.
  15. Hui J, Ren Y, Wang Y, Han Q. Lactobacillus acidophilus endophthalmitis postcataract operation: A case report with a literature review. Ocul Immunol Inflamm 2023.

See these in context on the Lactobacillus Acidophilus monograph →

Bifidobacterium Bifidum 7 references
  1. Pierce A. The American Pharmaceutical Association Practical Guide to Natural Medicines. New York: The Stonesong Press, 1999:19.
  2. Xiao JZ, Takahashi S, Odamaki T, et al. Antibiotic susceptibility of bifidobacterial strains distributed in the Japanese market. Biosci Biotechnol Biochem. 2010;74(2):336-42. PubMed
  3. Rerksuppaphol S, Rerksuppaphol L. Randomized controlled trial of probiotics to reduce common cold in schoolchildren. Pediatr Int. 2012;54(5):682-7. PubMed
  4. Karamali M, Dadkhah F, Sadrkhanlou M, et al. Effects of probiotic supplementation on glycaemic control and lipid profiles in gestational diabetes: a randomized, double-blind, placebo-controlled trial. Diabetes Metab 2016;42(4):234-41. PubMed
  5. Badehnoosh B, Karamali M, Zarrati M, et al. The effects of probiotic supplementation on biomarkers of inflammation, oxidative stress and pregnancy outcomes in gestational diabetes. J Matern Fetal Neonatal Med. 2018 May;31(9):1128-1136.
  6. Pruccoli G, Silvestro E, Pace Napoleone C, Aidala E, Garazzino S, Scolfaro C. Are probiotics safe? Bifidobacterium bacteremia in a child with severe heart failure. Infez Med. 2019;27(2):175-178.
  7. Esaiassen E, Hjerde E, Cavanagh JP, Simonsen GS, Klingenberg C; Norwegian Study Group on Invasive Bifidobacterial Infections. Bifidobacterium bacteremia: Clinical characteristics and a genomic approach to assess pathogenicity. J Clin Microbiol. 2017;55(7) PubMed

See these in context on the Bifidobacterium Bifidum monograph →

Streptococcus Thermophilus 21 references
  1. Saxelin M, Chuang NH, Chassy B, et al. Lactobacilli and bacteremia in southern Finland 1989-1992. Clin Infect Dis 1996;22:564-6. PubMed
  2. Tynkkynen S, Singh KV, Varmanen P. Vancomycin resistance factor of Lactobacillus rhamnosus GG in relation to enterococcal vancomycin resistance (van) genes. Int J Food Microbiol 1998;41:195-204. PubMed
  3. Klein G, Zill E, Schindler R, et al. Peritonitis associated with vancomycin-resistant Lactobacillus rhamnosus in a continuous ambulatory peritoneal dialysis patient; organism identification, antibiotic therapy, and case report. J Clin Microbiol 1998;36:
  4. Kalima P, Masterton RG, Roddie PH, et al. Lactobacillus rhamnosus infection in a child following bone marrow transplant. J Infect 1996;32:165-7. PubMed
  5. Goldin BR. Health Benefits of probiotics. Br J Nutr 1998;80:S203-7. DOI
  6. Rautio M, Jousimies-Somer H, Kauma H, et al. Liver abscess due to Lactobacillus rhamnosus strain indistinguishable from L. rhamnosus strain GG. Clin Infect Dis 1999;28:1159-60.
  7. MacGregor G, Smith AJ, Thakker B, Kinsella J. Yoghurt biotherapy: contraindicated in immunosuppressed patients? Postgrad Med J 2002;78:366-7. PubMed
  8. Land MH, Rouster-Stevens K, Woods CR, et al. Lactobacillus sepsis associated with probiotic therapy. Pediatrics 2005;115:178-81.
  9. De Groote MA, Frank DN, Dowell E, et al. Lactobacillus rhamnosus GG bacteremia associated with probiotic use in a child with short gut syndrome. Pediatr Infect Dis J 2005;24:278-80. PubMed
  10. Vahabnezhad E, Mochon AB, Wozniak LJ, Ziring DA. Lactobacillus bacteremia associated with probiotic use in a pediatric patient with ulcerative colitis. J Clin Gastroenterol. 2013;47(5):437-9. PubMed
  11. Dolatkhah N, Hajifaraji M, Abbasalizadeh F, Aghamohammadzadeh N, Mehrabi Y, Abbasi MM. Is there a value for probiotic supplements in gestational diabetes mellitus? A randomized clinical trial. J Health Popul Nutr. 2015;33:25. PubMed
  12. Pruccoli G, Silvestro E, Pace Napoleone C, Aidala E, Garazzino S, Scolfaro C. Are probiotics safe? Bifidobacterium bacteremia in a child with severe heart failure. Infez Med. 2019;27(2):175-178.
  13. Sendil S, Shrimanker I, Mansoora Q, Goldman J, Nookala VK. Lactobacillus rhamnosus bacteremia in an immunocompromised renal transplant patient. Cureus. 2020;12(2):e6887. PubMed
  14. Albarillo FS, Shah U, Joyce C, Slade D. Lactobacillus rhamnosus Infection: A single-center 4-year descriptive analysis. J Glob Infect Dis. 2020;12(3):119-123. PubMed
  15. Pasala S, Singer L, Arshad T, Roach K. Lactobacillus endocarditis in a healthy patient with probiotic use. IDCases. 2020;22:e00915. PubMed
  16. Agrawal S, Tuchman ES, Bruce MJ, Theodorou ME. Fatal Lactobacillus endocarditis in a patient with transcatheter aortic valve replacement. BMJ Case Rep. 2020;13(11):e236835.
  17. Antoun M, Hattab Y, Akhrass FA, Hamilton LD. Uncommon pathogen, Lactobacillus, causing infective endocarditis: Case report and review. Case Rep Infect Dis. 2020;2020:8833948. PubMed
  18. Rossi F, Amadoro C, Gasperi M, Colavita G. Lactobacilli infection case reports in the last three years and safety implications. Nutrients. 2022;14(6):1178. PubMed
  19. Franko B, Vaillant M, Recule C, Vautrin E, et al. Lactobacillus paracasei endocarditis in a consumer of probiotics. Med Mal Infect. 2013;43(4):171-3. PubMed
  20. Campbell RE, Miller A, Afroze A. Native valve endocarditis secondary to Lactobacillus paracasei bacteremia. Consultant. 2020;60(9):27-8. DOI
  21. Kato K, Funabashi N, Takaoka H, et al. Lactobacillus paracasei endocarditis in a consumer of probiotics with advanced and severe bicuspid aortic valve stenosis complicated with diffuse left ventricular mid-layer fibrosis. Int J Cardiol. 2016;224:157-161. PubMed

See these in context on the Streptococcus Thermophilus 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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