Drug & supplement interaction

Broccoli + Cephalexin

Cephalexin brand names: Keflex, Keftab, Cephalex, Lexin.

No Known Interaction
Medically reviewed by · Updated July 2026 · Pair last verified Sep 13, 2026
The bottom line No known interaction

We found no known interaction between Broccoli and Cephalexin in our sources. Absence of a documented interaction is not the same as proven safety, and does not guarantee one does not exist. Do not start, stop, or change a medication or supplement based on this page; confirm with your pharmacist or doctor first. Additionally, although there is no interaction, the two are separately associated with some of the same side effects, which would make a new symptom harder to attribute to one or the other.

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Interaction report

Broccoli and Cephalexin

We checked these two against our interaction database. Here is what we found.

No Known Interaction Found

We did not find a documented interaction between Cephalexin and Broccoli in our sources. This does not guarantee that the combination is completely free of risk — there is often limited research on supplements and herbal products, especially around drug interactions.

If you decide to take both, the practical routine is simple: add one new thing at a time and note the date you started it. If the combination is going to disagree with you, it usually shows in the first days to a couple of weeks — and a start date turns “I’ve been feeling off” into something a pharmacist can actually work with. Do not stop a prescribed medicine on your own.

Always talk with your pharmacist or doctor before making changes to your medications or supplements, particularly if you take several medications or have an ongoing health condition.

Broccoli safety at a glance

Broccoli overall Generally safe Broccoli as a food is safe for most people; concentrated supplements are less studied.
Pregnancy Likely Safe When used orally in food amounts. There is insufficient reliable information available about the safety of broccoli when used in medicinal amounts during pregna... Read the full pregnancy detail
Breastfeeding Likely Safe When used orally in food amounts. There is insufficient reliable information available about the safety of broccoli when used in medicinal amounts during pregna... Read the full breastfeeding detail

Pregnancy & breastfeeding ratings are from Natural Medicines (Therapeutic Research Center) — the full detail is in the Special populations card below. Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Cephalexin and Broccoli? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Cephalexin

Interactions in our licensed database are recorded against drug classes, not just single drug names. Cephalexin is filed under 7 classifications — including organic anion transporter 3 (oat3) substrates, organic anion transporter 1 (oat1) substrates, antibiotic drugs. Broccoli has documented interactions with 2 drug classes — the most serious being cytochrome p450 1a2 (cyp1a2) substrates (moderate) and cytochrome p450 2a6 (cyp2a6) substrates (moderate) — and none of Cephalexin’s classifications are among them.

Classification data comes from our licensed Natural Medicines dataset. A medication can belong to classes beyond those recorded there, so this describes how the check was run — it is not a safety guarantee.

Keep it in perspective

Broccoli Does Interact With Other Medications

Broccoli has 187 moderate known drug interactions in our database — Cephalexin isn’t one of them. If you take anything else, check it against the full list below.

Moderate 187 No known interaction 2,643 (incl. Cephalexin)
Taking anything else?

Check Another of Your Medications Against Broccoli

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

What to actually watch for

No Interaction Found — But Data Suggests Broccoli and Cephalexin May Share Several of the Same Side Effects

This is not an interaction. Neither one changes how your body handles the other, and nothing here says they react together. What our sources do show is that each has separately been linked to the effects below — so taking both can make those effects more likely to turn up, and harder to pin on one or the other if they do. One of them is worth acting on rather than waiting out — marked below.

  • An allergic reaction Worth acting on Additional detail

    Broccoli

    “Topically, allergic reactions to broccoli have caused contact dermatitis.”

    Broccoli · Natural Medicines adverse-effect record, reported in dermatitis.

    1 source cited
    1. 14158. Chakrabarti A, Prais L, Foulds IS. Allergic contact dermatitis to broccoli. Br J Dermatol 2003;148:172-3. PubMed

    Cephalexin

    Listed in the ADVERSE REACTIONS section of the FDA label for Cephalexin. Read the label on DailyMed ›

  • Stomach pain / Diarrhea Additional detail

    Broccoli

    “Orally, loose stools, diarrhea, abdominal pain, and abdominal cramping have been reported following intake of broccoli seed and sprout extracts, particularly at high doses.”

    Broccoli · Natural Medicines adverse-effect record, reported in diarrhea.

    1 source cited
    1. 114753. Bauman JE, Hsu CH, Centuori S, et al. Randomized Crossover Trial Evaluating Detoxification of Tobacco Carcinogens by Broccoli Seed and Sprout Extract in Current Smokers. Cancers (Basel). 2022;14(9):2129. Published 2022 Apr 24. PubMed

    Cephalexin

    Listed in the ADVERSE REACTIONS section of the FDA label for Cephalexin. Read the label on DailyMed ›

Reported for Broccoli but not commonly for Cephalexin: a skin rash.

Effects for Cephalexin come from the ADVERSE REACTIONS section of its FDA label; effects for Broccoli come from the Natural Medicines adverse-effect record, quoted above. Wording is matched across sources by our own clinical vocabulary, so treat this as a prompt to pay attention, not a diagnosis.

Special populations

Broccoli in Pregnancy & Breastfeeding

Pregnancy And Lactation Likely Safe

When used orally in food amounts. There is insufficient reliable information available about the safety of broccoli when used in medicinal amounts during pregnancy and lactation; avoid using.

DISCLAIMER: This tool is intended for informational purposes only, and should not be interpreted as specific medical advice. Patients should consult with a qualified healthcare provider before making decisions about therapies and/or health conditions.© 2026 Therapeutic Research Center

From our Q&A

Questions About Broccoli or Cephalexin

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Broccoli or Cephalexin, 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 Cephalexin

This page covers Broccoli only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Cephalexin page lists 61 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), African Wild Potato (moderate) and Aristolochia (moderate).

By severity: 3 major · 47 moderate · 11 minor.

From our pharmacist’s overview on the Cephalexin page

“Cephalexin (Keflex) is one of the most commonly prescribed oral antibiotics, usually for skin and urinary infections, and its supplement list warrants genuine care rather than a quick skim. Three of the 61 ingredients on file rate major.”

Reviewed by 2 · Jul 18, 2026

Open the Cephalexin interaction page

One more smart check

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

We hold 5,155 real supplement products containing Broccoli, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Broccoli. Even though Broccoli itself has no known interaction with Cephalexin, another ingredient on your label might. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Broccoli and Cephalexin 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 Broccoli
Top 5%

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

29 days ago today
Medication Cephalexin
Top 5%

#69 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.

Where does our data come from?
  • Source: the Natural Medicines (TRC Healthcare) clinical database — the evidence-graded professional reference for herb & supplement interactions.
  • Citation library: 103,510 references behind our interaction content, 65,311 of them resolved to verified PubMed/DOI sources. See every Broccoli reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The Broccoli and Cephalexin records this page draws on were last updated July 10, 2026.
  • What “no known interaction” means: no documented interaction in the sources above — not a guarantee of safety. Supplements are studied far less than prescription drugs, so we say exactly what the evidence supports, and nothing more.
Data structure & sourcing designed and verified by .
Supplement

About Broccoli

What is Broccoli?

  • General nutrition and antioxidant support
  • Heart and digestive health
  • Detoxification support
  • Cancer risk reduction (popular interest)
  • Blood sugar support

Broccoli is a nutritious cruciferous vegetable rich in fiber, vitamins, and plant compounds like sulforaphane that have drawn scientific interest for health benefits. Eating broccoli as food is safe and healthy for most people, but concentrated supplements and extracts are less studied and benefits are not firmly proven. Talk to your pharmacist or doctor before using broccoli supplements, especially in high doses.

Brassica oleracea var. italica · Brassicaceae · Florets, sprouts, seeds, and stalks · Whole vegetable (fresh, frozen, cooked), broccoli sprouts, powders, capsules, and sulforaphane or glucoraphanin extracts

An interaction check asks whether these two react with each other — it does not ask whether Broccoli is a good idea for someone in your situation. Here is what our Broccoli record says about it on its own.

Broccoli: dosing

There is no official or standardized supplement dose for broccoli. As a food, broccoli can simply be enjoyed as part of a balanced diet.For broccoli sprout and sulforaphane products, the amount of active compound varies a lot between brands, and a proven effective dose has not been established.

From our Broccoli monograph — the full record covers uses, side effects and every documented interaction.

Read the full Broccoli monograph & all interactions
Medication

About Cephalexin

What Is Cephalexin Used For?

Brand names: Keflex, Keftab, Cephalex, Lexin

Cephalexin treats bacterial infections caused by susceptible strains of bacteria. It is used for respiratory tract infections, ear infections (otitis media), skin and skin structure infections, bone infections, and genitourinary tract infections — including acute prostatitis.

It works only against bacterial infections — not viruses like colds or flu. Your prescriber should use it only when a bacterial infection is confirmed or strongly suspected, to help prevent antibiotic resistance.

Most-Reported Side Effects for Cephalexin

From FAERS, the FDA’s public side-effect reporting system (0 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Chronic kidney disease 2,157 reports
Renal failure 1,558 reports
Acute kidney injury 1,550 reports
Diarrhea 1,405 reports
Fatigue 1,303 reports
See full Cephalexin drug information
Keep checking

Other Drugs & Broccoli

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

0Major
187Moderate
0Minor
2,642No known interaction
187 Moderate 2,642 No interaction
Moderate

187 interactions

Showing 60 of 187 moderate interactions — see all 187 on the Broccoli page.

No interaction 2,642 drugs checked — show the list

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

Showing the 60 most looked-up of 2,642 medications checked with no known interaction — see the full Broccoli list.

See the full Broccoli interactions page
See every supplement checked against Cephalexin, ranked by severity
Evidence & sources

Broccoli References

The 5 references that drive our Broccoli monograph and interaction data, from the evidence-graded Natural Medicines (TRC Healthcare) database. Citations with a link open the study on PubMed or the publisher’s site.

  1. Kristal AR, Lampe JW. Brassica vegetables and prostate cancer risk: a review of the epidemiological evidence. Nutr Cancer 2002;42:1-9. PubMed
  2. Chakrabarti A, Prais L, Foulds IS. Allergic contact dermatitis to broccoli. Br J Dermatol 2003;148:172-3. PubMed
  3. Hakooz, N. and Hamdan, I. Effects of dietary broccoli on human in vivo caffeine metabolism: a pilot study on a group of Jordanian volunteers. Curr Drug Metab 2007;8(1):9-15. PubMed
  4. Kall MA, Vang O, Clausen J. Effects of dietary broccoli on human drug metabolising activity. Cancer Lett. 1997;114(1-2):169-70. PubMed
  5. Bauman JE, Hsu CH, Centuori S, et al. Randomized Crossover Trial Evaluating Detoxification of Tobacco Carcinogens by Broccoli Seed and Sprout Extract in Current Smokers. Cancers (Basel). 2022;14(9):2129. Published 2022 Apr 24. PubMed

Medication overviews come from MedlinePlus (NIH); supplement label data from the NIH Dietary Supplement Label Database. Content is written and reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.

Pharmacist Counseling Corner

Taking Broccoli and Cephalexin Together: Common Questions

Is it safe to take Broccoli with Cephalexin?
We do not list a known interaction between Broccoli and Cephalexin. That does not guarantee the combination is risk-free, so confirm with your pharmacist or doctor — especially if you take other medications or have a health condition.
Do Broccoli and Cephalexin have any of the same side effects?
Yes — our sources link each of them separately to 3 of the same effects. That is not an interaction: neither changes how your body handles the other. It does mean that if one of those effects turns up, it can be harder to tell which one is behind it. They are listed on this page with the source behind each.
How was the Broccoli and Cephalexin combination checked?
Interactions in our licensed database are recorded against drug classes. Cephalexin is filed under 7 classifications, and Broccoli has documented interactions with 2 drug classes — none of Cephalexin's classifications are among them. A medication can belong to classes beyond those recorded in our dataset, so this describes how the check was run rather than guaranteeing safety.
Does Broccoli interact with any other medications?
Yes. Broccoli has 187 documented drug interactions in our database — Cephalexin is simply not one of them. If you take anything else, it is worth checking each one; they are all listed on this page.
Does Cephalexin interact with any supplements?
Yes. Cephalexin has documented interactions with 61 supplements in our database — Broccoli is not one of them. The Cephalexin interaction page linked on this page lists every one, ranked by severity.

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

Where next

Keep Exploring

Broccoli monograph Uses, safety profile, and every drug interaction in one place Cephalexin drug information The full plain-English guide to this medication Cephalexin supplement interactions Every supplement checked against Cephalexin, ranked by severity Supplement interaction checker Check any supplement or product against your medications Browse medications A–Z Every drug we’ve checked against herbs & supplements References The 5 citations behind this page Ask a pharmacist Free, personal answer from our licensed team

Still Have a Question About Cephalexin and Broccoli?

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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.