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

Acidophilus Probiotic Blend label
See full label image
Capsule Category: Non-nutrient/non-botanical
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Acidophilus Probiotic Blend 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

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.

Jump to a section

Check Your Meds Against Acidophilus Probiotic Blend by 21st Century

Ask about any prescription or over-the-counter medication and we check it for interactions with Acidophilus Probiotic Blend by 21st Century — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
Prefer a human? Send your question to our licensed pharmacists — free, answered by email within 24 hours.
Computed from our clinical databases

HelloPharmacist Scorecard of Acidophilus Probiotic Blend by 21st Century

Four independent checks of what is known — a summary of the available information, not a grade of the product itself.

Evidence for Intended Use
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
Not assessable

The stated purpose hasn't been mapped to our evidence data yet.

Why this rating?
  • We haven't mapped this product's purpose to our evidence data yet — it'll be graded on the next content refresh.
Ingredient Transparency
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.
Known Interaction Concern
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.
Safety Information
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.

HelloPharmacist summaryFormula with limited ingredient disclosure with no assessable stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

Assessment coverage: 3 of 4 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Oct 23, 2020.

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
Net contents 100 Capsule(s)
Market status Off market
Date entered into DSLD Oct 23, 2020
DSLD ID 239327
Product type Non-nutrient/non-botanical
Supplement form Capsule
Dietary claims / uses All Other
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)
IngredientAmount% DV
Proprietary Blend175 mg--
Lactobacillus salivarius0 NP--
Lactobacillus acidophilus0 NP--
Bifidobacterium bifidum0 NP--
Streptococcus thermophilus0 NP--

Other ingredients: Whey, Fructooligosaccharide, Gelatin, Cellulose, Citrus Pectin, Silicon Dioxide, Magnesium Stearate

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

Precautions

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 a milk ingredient (whey).

Storage

Store at room temperature.

Formulation

No added sugar, salt, preservatives, artificial flavors or colors. Gluten free.

Super strength

Proprietary Blend designed to maintain healthy intestinal flora

Seals/Symbols

Laboratory Tested Guaranteed Quality

FDA Statement of Identity

Dietary Supplement

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

See for yourself

Acidophilus Probiotic Blend by 21st Century label

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

Acidophilus Probiotic Blend 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 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, Fructooligosaccharide, Gelatin, Cellulose, Citrus Pectin, Silicon Dioxide, Magnesium Stearate. These complete the product’s ingredient list but are not active constituents.

Interaction report

Acidophilus Probiotic Blend by 21st Century Drug Interactions

Acidophilus Probiotic Blend contains 4 ingredients, and 2 of them have known drug interactions. Altogether they interact with 182 medications. Here’s the picture, then you can look up your own drug.

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

Lactobacillus acidophilus 182
Bifidobacterium bifidum 182

Individual Drug Interactions

The ingredients in Acidophilus Probiotic Blend interact with 182 drugs. Click any drug to see the details.

2 of the 4 ingredients in Acidophilus Probiotic Blend interact with drugs. Each result below shows which ingredient is responsible. Lactobacillus acidophilus Bifidobacterium bifidum

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
Lactobacillus acidophilus full monograph & interactions

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
Bifidobacterium bifidum full monograph & interactions
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.

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
Go deeper

The Full Monographs Behind Acidophilus Probiotic Blend’s Ingredients

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

Herb & supplement monograph

Lactobacillus Acidophilus

Interacts with 182 drugs

Lactobacillus acidophilus is a 'friendly' bacterium used as a probiotic to support gut and vaginal health. It is generally well tolerated in healthy people, and there is reasonable evidence...

Read the full Lactobacillus Acidophilus monograph → Herb & supplement monograph

Bifidobacterium Bifidum

Interacts with 182 drugs

Bifidobacterium bifidum is a 'friendly' bacteria (probiotic) that naturally lives in the human gut and is taken to support digestion and gut balance. Some evidence suggests probiotics may he...

Read the full Bifidobacterium Bifidum monograph → Herb & supplement monograph

Streptococcus Thermophilus

Streptococcus thermophilus is a friendly bacterium used as a probiotic, often combined with other strains in yogurt and supplements. It is generally well tolerated in healthy people and may...

Read the full Streptococcus Thermophilus monograph →
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

Keep exploring
Supplement interaction checker › Check any supplement or product against your medications Drug–drug interactions › Check two or more of your medications against each other Browse medications A–Z › Every drug we've checked against herbs & supplements NDC & pricing lookup › Find a drug’s NDCs, packaging and costs Ask a pharmacist › Free, personal answer from our licensed team