Interactions on record — worth a quick check against your medications. Based on 1 of 4 ingredients. Check your meds →
Dietary supplement

Four Strain Lactobacilli Ingredients & Drug Interactions

by Custom Probiotics

Four Strain Lactobacilli label
See full label image
Powder Category: Non-nutrient/non-botanical
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 23, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Four Strain Lactobacilli 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

Four Strain Lactobacilli is a dietary supplement by Custom Probiotics 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 L. acidophilus. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Four Strain Lactobacilli by Custom Probiotics

Ask about any prescription or over-the-counter medication and we check it for interactions with Four Strain Lactobacilli by Custom Probiotics — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Four Strain Lactobacilli by Custom Probiotics

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 30, 2026

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.

This powder contains four strains of live Lactobacillus bacteria: L. rhamnosus, L. salvarius, L. acidophilus, and L. plantarum. These are probiotics — beneficial bacteria meant to support your gut health.

The product contains no inactive ingredients listed.

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: digestive health and gut flora balance.
  • We looked for evidence on: Antibiotic-associated diarrhea, Bacterial vaginosis, Clostridioides difficile infection, Constipation, Inflammatory bowel disease (IBD), Irritable bowel syndrome (IBS) — 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: Lactobacillus Acidophilus is rated "Insufficient Reliable Evidence To Rate" for Constipation, Inflammatory bowel disease (IBD), Lactose intolerance, Rotaviral diarrhea.

L. acidophilus is rated possibly effective for irritable bowel syndrome (IBS), Helicobacter pylori infection, antibiotic-associated diarrhea, and bacterial vaginosis. It's rated possibly ineffective for atopic disease (allergic conditions), and we don't have enough reliable evidence to rate it for acute respiratory distress syndrome.

We hold no effectiveness data for the other three strains in this product.

The evidence, ingredient by ingredient Lactobacillus Acidophilus

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.

L. acidophilus is generally well tolerated in healthy adults and children. In clinical trials, digestive side effects like stomach discomfort, bloating, flatulence, and diarrhea can occur when probiotics are taken by mouth, but these are uncommon.

There's a theoretical concern that live L. acidophilus could cause serious infections (bacteremia, sepsis, abscess, or meningitis) in people with certain medical conditions, though most reported cases involve bacteria that translocated from other parts of the body. For pregnancy, L. acidophilus is rated possibly safe, though data are limited — talk with your doctor about whether it's right for you.

We hold no lactation safety data for this ingredient.

Side effects, ingredient by ingredient Lactobacillus Acidophilus

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?
  • 1 of the 1 matched ingredient can interact with medications — Lactobacillus Acidophilus.
  • 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.

Check your antibiotic medications before starting this product — the live organisms in L. acidophilus can be killed by antibiotics, reducing the probiotic's effectiveness. Your doctor or pharmacist can help you space them properly.

We could not check the other three strains in the product, so if you take any prescription medications, run them through the checker on this page to be sure.

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 four-strain probiotic may be worth considering if you have IBS, antibiotic-associated diarrhea, or related digestive concerns — L. acidophilus shows some promise for those. If you take antibiotics, space them apart from this product and discuss the timing with your doctor or pharmacist.

Anyone with a compromised immune system or serious underlying illness should check with their healthcare provider first, since live probiotics carry a small theoretical risk in vulnerable patients.

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

Assessment coverage: 1 of 4 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Sep 21, 2018.

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 Four Strain Lactobacilli, straight from the product label.

Brand Custom Probiotics
Net contents 0 Not Present
Market status On market
Date entered into DSLD Sep 21, 2018
DSLD ID 181317
Product type Non-nutrient/non-botanical
Supplement form Powder
Dietary claims / uses All Other
Intended target group(s) Adult (18 - 50 Years), Children (All), Gluten Free, Dairy Free, Sugar 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 Four Strain Lactobacilli by Custom Probiotics, 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:
0.1 Gram(s)
Maximum serving Sizes:
1.6 Gram(s)
IngredientAmount% DV
L. rhamnosus0 NP--
L. salvarius0 NP--
L. acidophilus0 NP--
L. plantarum0 NP--

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 of use: Dissolve 1-2 scoops (enclosed) of the dairy-free probiotic powder in one glass of purified water and drink it. Do this first thing in the morning and/or at bedtime.

Please read enclosed dosage suggestion or visit www.customprobiotics.com

Storage

Bottles should be kept tightly closed and stored in the refrigerator to retain maximum potency.

Formulation

Does not contain: Artificial colors, flavors, preservatives, sugar, gluten, soy, wheat or FOS.

Dairy free probiotic powder

General Statements

Ultra potency

260 billion cfu's per gram

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

See for yourself

Four Strain Lactobacilli by Custom Probiotics label

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

Four Strain Lactobacilli 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 Four Strain Lactobacilli by Custom Probiotics

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

Serving size0.1 Gram(s) Dosage formPowder 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.

L. rhamnosus

0 NP per serving

L. salvarius

0 NP per serving

L. acidophilus

Interacts with
182 drugs
0 NP per serving

Lactobacillus acidophilus is a 'friendly' bacterium used as a probiotic to support gut and vaginal health. It is generally well tolerated in healthy p...

L. acidophilus monograph & interactions

L. plantarum

0 NP per serving
Interaction report

Four Strain Lactobacilli by Custom Probiotics Drug Interactions

Want to check YOUR meds against Four Strain Lactobacilli?

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

L. acidophilus 182

Individual Drug Interactions

The ingredients in Four Strain Lactobacilli interact with 182 drugs. Click any drug to see the details.

1 of the 4 ingredients in Four Strain Lactobacilli interact with drugs. Each result below shows which ingredient is responsible. L. acidophilus

Each ingredient & the kinds of drugs it affects

For each ingredient in Four Strain Lactobacilli 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.

L. 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
L. acidophilus full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Four Strain Lactobacilli, from the product label.

Custom Probiotics

See all Custom Probiotics products
Name
Custom Probiotics, Inc.
City
Glendale
State
California
ZipCode
91214
Phone Number
(800) 219-8405
Web Address
www.customprobiotics.com
Pharmacist Counseling Corner

Four Strain Lactobacilli by Custom Probiotics: Common Questions

Does Four Strain Lactobacilli by Custom Probiotics interact with any medications?
Yes. Based on its ingredients, Four Strain Lactobacilli 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?
Four Strain Lactobacilli 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.
Does L. acidophilus actually help with IBS?
It's rated possibly effective for IBS, which means there's some evidence it may help, but the data aren't ironclad yet. Results vary from person to person, so you might want to try it for a few weeks and see if your symptoms improve — and chat with your doctor about whether it makes sense for your situation.
Can I take this with my antibiotics?
Antibiotics will kill the live bacteria in this probiotic, so taking them together defeats the purpose. Space them apart — your doctor or pharmacist can tell you how many hours to leave between them. Most people wait at least 2-3 hours, but check on your specific antibiotic.
What are the side effects?
Most people tolerate L. acidophilus well. Digestive side effects like bloating, gas, stomach discomfort, or loose stools can happen when you first start probiotics, but they're uncommon and usually mild. In rare cases, live probiotics can cause serious infections in people with weakened immune systems.
Is it safe to take while pregnant?
L. acidophilus is rated possibly safe in pregnancy, though data are limited. Talk with your doctor or midwife before starting — they know your health and can give you personalized advice.
What exactly is in this powder?
It contains four live Lactobacillus strains: L. rhamnosus, L. salvarius, L. acidophilus, and L. plantarum. These are beneficial bacteria meant to support your gut microbiome. There are no fillers or other inactive ingredients.
How do I know if this will work for me?
L. acidophilus is possibly effective for IBS, antibiotic-associated diarrhea, bacterial vaginosis, and H. pylori infection — so if you have one of those, there's a reasonable chance it might help. For other uses, the evidence is weaker or absent. Give it a few weeks and see whether you notice improvement.

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

Not sure if Four Strain Lactobacilli is safe with your meds?

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Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

Four Strain Lactobacilli label
Go deeper

The Full Monographs Behind Four Strain Lactobacilli’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 →
Sources

Sources & How We Checked

Four Strain Lactobacilli'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 15 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 →

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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