Drug & supplement interaction

Aloe + Ondansetron

Ondansetron brand name: Zofran.

Minor Interaction
The bottom line Minor

Aloe has a minor interaction with Ondansetron. Theoretically, aloe might decrease the levels and clinical effects of CYP1A2 substrates.

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

Aloe and Ondansetron

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

Minor

CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES

Why this applies to Ondansetron

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

Theoretically, aloe might decrease the levels and clinical effects of CYP1A2 substrates.
In vitro research shows that aloe extract induces CYP1A2 enzymes.
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 for ondansetron (Zofran): your liver uses an enzyme called CYP1A2 (among others) to break this medicine down. The concern on file is that aloe, taken by mouth, might speed that enzyme up a bit. If it did, your body could clear ondansetron a little faster, which in theory might make it work less well at keeping nausea and vomiting under control.

Honestly, I wouldn't lose sleep over this one. This is rated a minor interaction, and the only evidence comes from lab and test-tube studies, not real people. We don't actually know if it matters in everyday life. Still, if you're using oral aloe regularly and rely on Zofran, it's worth a quick chat with your pharmacist or doctor.

References
  1. Haron MH, Dale O, Martin K, et al. Evaluation of the Herb-Drug Interaction Potential of Commonly Used Botanicals on the US Market with Regard to PXR- and AhR-Mediated Influences on CYP3A4 and CYP1A2. J Diet Suppl 2022. 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

Aloe Also Interacts With Other Medications

Aloe has 1 major, 304 moderate, 155 minor 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.

Taking anything else?

Check Another of Your Medications Against Aloe

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

From our Q&A

Questions About Aloe 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 Aloe 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 Aloe 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 Aloe as Part of a Dietary Supplement Product? Check It for Interactions

We hold 1,978 real supplement products containing Aloe, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Aloe. Your product may carry other ingredients that interact with Ondansetron too, on top of Aloe — 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 Aloe 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 Aloe
Top 10%

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

29 days ago today
Medication Ondansetron
Top 5%

#96 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 Aloe

What is Aloe?

Aloe
  • Minor burns and skin irritation
  • Wound healing
  • Constipation
  • Skin hydration and moisturizing
  • Digestive complaints
  • Hair and scalp care

Aloe vera gel is widely used on the skin for minor burns and irritation, and some research suggests it may help. Aloe latex (the yellow part) is a strong laxative that can cause cramping and is not considered safe for regular use. Talk to your pharmacist or doctor before taking aloe by mouth, and avoid oral aloe during pregnancy.

Read the full Aloe 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 & Aloe

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

1Major
304Moderate
155Minor
2,369No known interaction
Major

1 interaction

Moderate

304 interactions

Showing 60 of 304 moderate interactions — see all 304 on the Aloe page.

Minor

155 interactions

Showing 60 of 155 minor interactions — see all 155 on the Aloe page.

No interaction 2,369 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 Aloe and Ondansetron Together: Common Questions

Can you take Aloe with Ondansetron?
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 Aloe and Ondansetron 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 Ondansetron and Aloe?

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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.