Drug & supplement interaction

Cauliflower + Ondansetron

Ondansetron brand name: Zofran.

Moderate Interaction
Medically reviewed by · Updated September 2026
The bottom line Moderate

Cauliflower has a moderate interaction with Ondansetron. Preliminary clinical evidence suggests that eating cruciferous vegetables, including broccoli, cauliflower, daikon radish sprouts, and cabbage, can increase cytochrome P450 1A2 (CYP1A2) activity by 14% to 27%.

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

Cauliflower and Ondansetron

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

Moderate

CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES

Why this applies to Ondansetron

Ondansetron falls under CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES — the group Cauliflower interacts with.

Preliminary clinical evidence suggests that eating cruciferous vegetables, including broccoli, cauliflower, daikon radish sprouts, and cabbage, can increase cytochrome P450 1A2 (CYP1A2) activity by 14% to 27%. Theoretically, cauliflower might increase the clearance and decrease the effects of drugs metabolized by CYP1A2. Some drugs metabolized by CYP1A2 include clozapine (Clozaril), cyclobenzaprine (Flexeril), fluvoxamine (Luvox), haloperidol (Haldol), imipramine (Tofranil), mexiletine (Mexitil), olanzapine (Zyprexa), pentazocine (Talwin), propranolol (Inderal), tacrine (Cognex), theophylline, zileuton (Zyflo), zolmitriptan (Zomig), and others.
Severity Moderate Likelihood Possible Evidence B

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 situation with cauliflower and your ondansetron (Zofran). Cruciferous veggies like cauliflower can nudge up the activity of a liver enzyme called CYP1A2, which is one of the enzymes that helps clear ondansetron from your body. In theory, speeding up that enzyme could clear the drug a little faster and make it slightly less effective at preventing nausea and vomiting.

Now, the honest part: this is based on weak, preliminary evidence, and ondansetron is also broken down by other pathways, so any real-world effect from cauliflower is likely small. Normal amounts on your dinner plate aren't something I'd worry about. If you're relying on Zofran to control bad nausea and it doesn't seem to be working, mention it to your pharmacist or doctor rather than changing anything yourself.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Peterson S, Schwarz Y, Li SS, et al. CYP1A2, GSTM1, and GSTT1 polymorphisms and diet effects on CYP1A2 activity in a crossover feeding trial. Cancer Epidemiol Biomarkers Prev 2009;18(11):3118-25.

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

Cauliflower Also Interacts With Other Medications

Cauliflower has 185 moderate known drug interactions in our database — the Ondansetron one above is one of them. If you take anything else, check it against the full list below.

Moderate 185 No known interaction 2,645 (incl. Ondansetron)
Taking anything else?

Check Another of Your Medications Against Cauliflower

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

From our Q&A

Questions About Cauliflower or Ondansetron

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Cauliflower or Ondansetron, not necessarily both, but if one is close to what you were about to ask it will usually go further than a database entry can:

Not quite your question? Ask our pharmacists directly — it is free, there is no account required, and answers usually come back within 24 hours.

Everything else you take

See Every Supplement That Interacts With Ondansetron

This page covers Cauliflower only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Ondansetron page lists 195 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Grapefruit (major), Lithium (major), St. John's Wort (major) and 1,3-dmaa (moderate).

By severity: 4 major · 145 moderate · 46 minor.

From our pharmacist’s overview on the Ondansetron page

“Ondansetron (Zofran) often stands between you and relentless nausea from chemotherapy or surgery, so read this page carefully. Four of the 195 ingredients rate major.”

Reviewed by 2 · Jul 18, 2026

Open the Ondansetron interaction page

One more smart check

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

We hold 1,705 real supplement products containing Cauliflower, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Cauliflower. Your product may carry other ingredients that interact with Ondansetron too, on top of Cauliflower — 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 Cauliflower and Ondansetron 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 Cauliflower
Top 25%

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

29 days ago today
Medication Ondansetron
Top 5%

#98 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 Cauliflower

What is Cauliflower?

  • General nutrition and a low-carb vegetable
  • Source of vitamin C and fiber
  • Antioxidant support
  • Digestive and gut health
  • Part of a heart-healthy diet

Cauliflower is a nutritious cruciferous vegetable that provides vitamin C, fiber, and plant compounds called glucosinolates. As a food it is healthy and safe for most people, but there is no strong proof that cauliflower supplements treat or prevent any specific disease. Enjoy it as part of a balanced diet rather than relying on pills.

Read the full Cauliflower monograph & all interactions
Medication

About Ondansetron

What Is Ondansetron Used For?

Brand name: Zofran

Ondansetron is used to prevent nausea and vomiting in several situations. Oral forms (tablets, orally disintegrating tablets, and oral solution) are approved to prevent nausea and vomiting from highly or moderately emetogenic (nausea-causing) cancer chemotherapy, from radiation therapy to the abdomen or whole body, and from surgery.

Ondansetron injection (given intravenously or intramuscularly in a clinical setting) is approved to prevent nausea and vomiting from emetogenic cancer chemotherapy — including high-dose cisplatin — in adults and children as young as 6 months old, as well as to prevent postoperative nausea and vomiting.

See full Ondansetron drug information
Keep checking

Other Drugs & Cauliflower

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

0Major
185Moderate
0Minor
2,644No known interaction
185 Moderate 2,644 No interaction
Moderate

185 interactions

Showing 60 of 185 moderate interactions — see all 185 on the Cauliflower page.

No interaction 2,644 drugs checked — show the list

We also checked Cauliflower against these medications and found no known interaction in our sources. Open any page to confirm.

Showing the 60 most looked-up of 2,644 medications checked with no known interaction — see the full Cauliflower list.

See the full Cauliflower interactions page
See every supplement checked against Ondansetron, ranked by severity
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

Keep exploring
Cauliflower monograph › Uses, safety, and every drug interaction in one place Ondansetron supplement interactions › Every supplement checked against Ondansetron, ranked by severity Ondansetron drug information › The full plain-English guide to this medication Supplement interaction checker › Check any supplement or product against your medications Browse medications A–Z › Every drug we've checked against herbs & supplements Ask a pharmacist › Free, personal answer from our licensed team
Pharmacist Counseling Corner

Taking Cauliflower and Ondansetron Together: Common Questions

Can you take Cauliflower with Ondansetron?
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 Cauliflower and Ondansetron 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 Ondansetron and Cauliflower?

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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.