Drug & supplement interaction

Soy + Dicloxacillin Sodium

Dicloxacillin Sodium brand names: Dynapen, Pathocil, Dycill, Pathocil Injection.

Minor Interaction
The bottom line Minor

Soy has a minor interaction with Dicloxacillin Sodium. Theoretically, antibiotics may decrease the activity of soy isoflavones.

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

Soy and Dicloxacillin Sodium

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

Minor

ANTIBIOTIC DRUGS

Why this applies to Dicloxacillin Sodium

Dicloxacillin Sodium falls under ANTIBIOTIC DRUGS — the group Soy interacts with.

Theoretically, antibiotics may decrease the activity of soy isoflavones.
Intestinal bacteria are responsible in part for converting soy isoflavones into their active forms. Antibiotics may decrease the amount of intestinal bacteria and decrease its ability to convert isoflavones.
Severity Minor Likelihood Possible Evidence D

Interaction 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.

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

Here's the gist of this one, and it's a mild concern that runs in an unexpected direction. The worry isn't that soy changes how dicloxacillin works. It's the other way around. Your gut bacteria help turn soy isoflavones into their more active forms, and an antibiotic like dicloxacillin can temporarily knock down some of those helpful bacteria. So while you're on it, your body may get a little less benefit from the soy itself.

Honestly, this is theoretical and only based on lab-type evidence, so I wouldn't lose sleep over it. Dicloxacillin still treats your infection just fine, and eating soy foods is safe alongside it. If you take concentrated soy isoflavone supplements for a specific reason, just mention it to your pharmacist or doctor.

References
  1. Morito K, Hirose T, Kinjo J, et al. Interaction of phytoestrogens with estrogen receptors alpha and beta. Biol Pharm Bull 2001;24:351-6. 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

Soy Also Interacts With Other Medications

Soy has 9 major, 343 moderate, 258 minor known drug interactions in our database — the Dicloxacillin Sodium 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 Soy

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

Everything else you take

See Every Supplement That Interacts With Dicloxacillin Sodium

This page covers Soy only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Dicloxacillin Sodium page lists 56 supplements it has a documented interaction with, worst first, each one explained.

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

By severity: 3 major · 42 moderate · 11 minor.

From our pharmacist’s overview on the Dicloxacillin Sodium page

“The riskiest pairing on this page is Siberian cocklebur with dicloxacillin (Dynapen), an antibiotic for staph skin and soft tissue infections. Both can stress the kidneys, and that additive strain accounts for one of the three major ratings among 56 supplements here, enough that this list warrants real care.”

Reviewed by 2 · Jul 18, 2026

Open the Dicloxacillin Sodium interaction page

One more smart check

Taking Soy as Part of a Dietary Supplement Product? Check It for Interactions

We hold 821 real supplement products containing Soy, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Soy. Your product may carry other ingredients that interact with Dicloxacillin Sodium too, on top of Soy — and those would not show on this page. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Soy and Dicloxacillin Sodium 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 Soy
Top 25%

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

29 days ago today
Medication Dicloxacillin Sodium
Steady interest

#1,650 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 Soy

What is Soy?

  • Menopause symptoms (hot flashes)
  • Heart and cholesterol health
  • Bone health
  • Plant-based protein source
  • General nutrition

Soy is a nutritious bean that is a staple food and a popular source of plant protein and isoflavones. Eating soy foods as part of a balanced diet is generally considered safe for most people, and there is moderate evidence it may modestly help cholesterol and some menopause symptoms, though results vary. Talk with your pharmacist or doctor before using concentrated soy isoflavone supplements, especially if you have a history of hormone-sensitive conditions.

Read the full Soy monograph & all interactions
Medication

About Dicloxacillin

What Is Dicloxacillin Used For?

Brand names: Dynapen, Pathocil, Dycill, Pathocil Injection

Dicloxacillin Sodium capsules are used to treat infections caused by staphylococci (staph bacteria) that produce an enzyme called penicillinase, which makes them resistant to ordinary penicillin. It works specifically against these resistant staph strains.

It should not be used for infections caused by bacteria that are still susceptible to regular penicillin G, or for infections caused by organisms other than resistant staphylococci. Lab cultures are used to confirm the right bug is being targeted.

See full Dicloxacillin drug information
Keep checking

Other Drugs & Soy

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

9Major
343Moderate
258Minor
2,219No known interaction
Major

9 interactions

Moderate

343 interactions

Showing 60 of 343 moderate interactions — see all 343 on the Soy page.

Minor

258 interactions

Showing 60 of 258 minor interactions — see all 258 on the Soy page.

No interaction 2,219 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 Soy and Dicloxacillin Sodium Together: Common Questions

Can you take Soy with Dicloxacillin Sodium?
There is only a minor interaction, which is usually not serious. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Soy and Dicloxacillin Sodium interaction?
We rate it Minor. This interaction is generally not clinically significant, but it remains worth noting and discussing with your pharmacist.

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

Still Have a Question About Dicloxacillin Sodium and Soy?

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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.