Drug & supplement interaction

Fermented Milk + Aztreonam

Aztreonam brand name: Azactam.

Moderate Interaction
The bottom line Moderate

Fermented Milk has a moderate interaction with Aztreonam. 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 Aztreonam

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

Moderate

ANTIBIOTIC DRUGS

Why this applies to Aztreonam

Aztreonam 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 simple version: this isn't a case where fermented milk changes how aztreonam works in your body. It's the other way around. Aztreonam is an antibiotic, and its whole job is to kill bacteria. The live probiotic bugs (like lactobacilli and bifidobacteria) in yogurt and other fermented milk are bacteria too, so the antibiotic can wipe out some of them before they ever do you any good.

So your aztreonam will still fight your infection just fine, you may just get less probiotic benefit. A common tip is to space them about 2 hours apart so they don't overlap. This is theory-based, not a dangerous interaction, but check with your pharmacist if you're relying on those probiotics.

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 Aztreonam 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 Aztreonam

This page covers Fermented Milk only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Aztreonam page lists 27 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Bacillus Coagulans (moderate), Bacillus Subtilis (moderate), Bifidobacterium Animalis Subsp. Lactis (moderate), Bifidobacterium Bifidum (moderate) and Bifidobacterium Breve (moderate).

By severity: 26 moderate · 1 minor.

From our pharmacist’s overview on the Aztreonam page

“Every entry on this page tells one story, and it is a gentler one than most interaction lists. Aztreonam (Azactam) is an injectable or inhaled antibiotic used for serious infections, often in people with cystic fibrosis, and none of these 27 supplement pairings makes the drug itself riskier or weaker.”

Reviewed by 2 · Jul 18, 2026

Open the Aztreonam interaction page

How much people look this up

Where Fermented Milk and Aztreonam 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

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

29 days ago today
Medication Aztreonam
Steady interest

#2,174 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
Medication

About Aztreonam Injection

What Is Aztreonam Injection Used For?

Brand name: Azactam

Azactam (aztreonam for injection) is used to treat infections caused by susceptible gram-negative bacteria. It is approved for urinary tract infections (including kidney infections and bladder infections), lower respiratory tract infections (including pneumonia), bloodstream infections (septicemia), skin and skin-structure infections (including those related to wounds, ulcers, and burns), intra-abdominal infections (including peritonitis), and gynecologic infections (including endometritis and pelvic cellulitis).

Azactam is also used alongside surgery to manage infections such as abscesses and infections involving perforated organs. In seriously ill patients who may also have gram-positive bacterial infections, it is often started together with another antibiotic that covers those bacteria. When anaerobic bacteria (bacteria that don't need oxygen) are also suspected, an anti-anaerobic antibiotic is added as well.

See full Aztreonam Injection drug information
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 Aztreonam Together: Common Questions

Can you take Fermented Milk with Aztreonam?
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 Aztreonam 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

Still Have a Question About Aztreonam and Fermented Milk?

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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.