Drug & supplement interaction

Fermented Milk + Piperacillin , Tazobactam

Piperacillin , Tazobactam brand name: Zosyn.

Moderate Interaction
The bottom line Moderate

Fermented Milk has a moderate interaction with Piperacillin , Tazobactam. Theoretically, antibiotic drugs might decrease the effectiveness of fermented milk.

Read the full interaction report
SeverityModerate
LikelihoodProbable
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Fermented Milk and Piperacillin , Tazobactam

Here is the interaction we found between these two, with the evidence behind it.

Moderate

ANTIBIOTIC DRUGS

Why this applies to Piperacillin , Tazobactam

Piperacillin , Tazobactam falls under ANTIBIOTIC DRUGS — the group Fermented Milk interacts with.

Theoretically, antibiotic drugs might decrease the effectiveness of fermented milk.
Some fermented milk preparations contain live and active organisms, including lactobacilli and bifidobacteria strains. Simultaneously taking antibiotics might kill a significant number of these organisms. Tell patients to separate administration of antibiotics and fermented milk preparations by at least 2 hours.
Severity Moderate Likelihood Probable Evidence D

Interaction has not been documented in well-controlled studies, however, the interaction has been demonstrated in some small human studies or in controlled animal studies in conjunction with multiple case reports..

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

Here's the thing to keep in mind: this interaction works the other way around from what most people expect. Piperacillin/Tazobactam (Zosyn) is a strong antibiotic, and it isn't affected by your fermented milk at all. Instead, the antibiotic can knock out the friendly probiotic bacteria (like lactobacilli and bifidobacteria) in things like yogurt or kefir, which means you may not get the gut-health perks you were hoping for.

This is more of a theoretical concern based on how these germ-killers work, not something proven to cause harm. The bigger point is that Zosyn is given by IV in a hospital or clinic, so timing food usually isn't an issue. If you're using a probiotic supplement, you can simply space it a couple of hours apart. Always check with your pharmacist or doctor first.

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

What These Ratings Mean

Every interaction above is graded three ways — here’s the key to each label.

Severity how clinically significant the interaction is
Major

Clinically significant. Avoid the combination, or use only under close professional supervision.

Moderate

Usually worth avoiding or managing — may need monitoring, a dose change, or timing apart.

Minor

Generally not serious. Be aware of it and mention it to your pharmacist.

Likelihood how strong the evidence is that the interaction actually happens in people
  • LikelyWell-controlled human studies have demonstrated the likely existence of this interaction.
  • ProbableInteraction has not been documented in well-controlled studies, however, the interaction has been demonstrated in some small human studies or in controlled animal studies in conjunction with multiple case reports.
  • PossibleInteraction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.
  • UnlikelyInteraction has been demonstrated in animal or in lab research but has been shown not to occur in humans.
Evidence the quality of the studies behind the rating (graded A–D)
  • AHigh-quality meta-analysis (quantitative systematic review).
  • BCase-control study.
  • CConsensus.
  • DAnecdotal evidence.

These ratings are for information only. Never start, stop, or otherwise change your therapy before speaking with your provider.

Keep it in perspective

Fermented Milk Also Interacts With Other Medications

Fermented Milk has 473 moderate known drug interactions in our database — the Piperacillin , Tazobactam one above is one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Fermented Milk

Covers the 2,830 medications we’ve checked against Fermented Milk. Pick one to open its full report.

Everything else you take

See Every Supplement That Interacts With Piperacillin , Tazobactam

This page covers Fermented Milk only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Piperacillin , Tazobactam page lists 39 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Asarabacca (major), Siberian Cocklebur (major), Aristolochia (moderate), Bacillus Coagulans (moderate) and Bacillus Subtilis (moderate).

By severity: 2 major · 35 moderate · 2 minor.

From our pharmacist’s overview on the Piperacillin , Tazobactam page

“Piperacillin with tazobactam (Zosyn) is a powerful IV antibiotic used for serious infections, often in people who are already quite sick, and I would handle the two major-rated entries on this list with genuine care. Both involve kidney harm: Siberian cocklebur, and asarabacca, which is often contaminated with aristolochic acid, a kidn…”

Reviewed by 2 · Jul 18, 2026

Open the Piperacillin , Tazobactam interaction page

How much people look this up

Where Fermented Milk and Piperacillin , Tazobactam Sit Against Everything Else

Out of every supplement and medication people look up on HelloPharmacist, here is where these two land this week — and which way each has been moving.

Supplement Fermented Milk
Top half

#429 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Piperacillin , Tazobactam
Steady interest

#1,779 of 2,830 medications looked up here in the last 7 days

29 days ago today

Position among everything looked up on this site, not a measure of how commonly either one is used or how important it is. A supplement can climb this list because of a news story. It counts every request to the page, automated ones included, and nothing here identifies anyone.

Supplement

About Fermented Milk

What is Fermented Milk?

  • Digestive health
  • Supporting gut bacteria (probiotics)
  • Lactose-related digestive discomfort
  • General nutrition (protein, calcium)
  • Immune support
  • Diarrhea prevention

Fermented milk is a food made by culturing milk with helpful bacteria or yeast, and it provides protein, calcium, and probiotics. It is generally safe for most people and may help digestion and gut health, though benefits depend on the product and strains used. People with milk allergy or weakened immune systems should be cautious.

Read the full Fermented Milk monograph & all interactions
Keep checking

Other Drugs & Fermented Milk

Browse every other medication we’ve checked against Fermented Milk — both the ones with a known interaction and the ones without. Select any drug for the full detail.

0Major
473Moderate
0Minor
2,356No known interaction
Moderate

473 interactions

Showing 60 of 473 moderate interactions — see all 473 on the Fermented Milk page.

No interaction 2,356 drugs checked — show the list
Sources

Sources & How We Checked

Interaction details are evidence-graded and sourced from the Natural Medicines database. The medication overview comes from MedlinePlus.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

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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Pharmacist Counseling Corner

Taking Fermented Milk and Piperacillin , Tazobactam Together: Common Questions

Can you take Fermented Milk with Piperacillin , Tazobactam?
There is a moderate interaction, so it may be acceptable with monitoring or timing changes — but check with your pharmacist first. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Fermented Milk and Piperacillin , Tazobactam interaction?
We rate it Moderate. This combination may require monitoring, a dose adjustment, or separating the times you take each one. Consult your pharmacist before using them together.

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

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This information is for education only and is not a substitute for professional medical advice. Always check with your pharmacist or doctor before starting, stopping, or combining supplements and medications.