Drug & supplement interaction

Arum + Orlistat

Orlistat brand names: Xenical, Alli.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Arum and Orlistat 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

Arum and Orlistat

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 Orlistat and Arum 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.

Arum safety at a glance

Arum overall Avoid The raw plant is toxic and irritating, and safe doses have not been established.
Pregnancy Likely Unsafe When used orally because of its toxicity; avoid using. Read the full pregnancy detail
Breastfeeding Likely Unsafe When used orally because of its toxicity; avoid using. 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 Orlistat and Arum? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Orlistat

Interactions in our licensed database are recorded against drug classes, not just single drug names. Orlistat is filed under 2 classifications — including oral drugs. Arum has documented interactions with 1 drug class — the most serious being iron (minor) — and none of Orlistat’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

Arum Does Interact With Other Medications

Arum has 1 minor known drug interaction in our database — Orlistat isn’t one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Arum

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

What to actually watch for

No Interaction Found — But Data Suggests Arum and Orlistat 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.

  • Diarrhea / Swelling / Vomiting reported in 7.6% of FDA reports for Orlistat Additional detail

    Arum

    “Orally, arum has been reported to cause burning of the oral mucous membranes, likely due to its oxalate crystal content. The immediate burning sensation caused by arum is thought to limit its oral intake, possibly reducing the likelihood for arum toxicity. Arum has also been reported to cause bloody vomiting, bloody diarrhea, and swelling of the tongue, lips, and palate in some people (18,32466).”

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

    3 sources cited
    1. 101417. Prakash Raju KNJ, Goel K, Anandhi D, Pandit VR, Surendar R, Sasikumar M. Wild tuber poisoning: Arum maculatum - A rare case report. Int J Crit Illn Inj Sci. 2018;8(2):111-114. PubMed
    2. 18. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.
    3. 32466. Mrvos, R., Dean, B. S., and Krenzelok, E. P. Philodendron/dieffenbachia ingestions: are they a problem? J Toxicol Clin Toxicol 1991;29(4):485-491. PubMed

    Orlistat

    Listed in the ADVERSE REACTIONS section of the FDA label for Orlistat, and in voluntary FDA adverse-event reports. Read the label on DailyMed ›

Effects for Orlistat come from the ADVERSE REACTIONS section of its FDA label; effects for Arum come from the Natural Medicines adverse-effect record, quoted above. Where a percentage is shown, it is the share of 25,755 voluntary FDA FAERS reports for Orlistat that mention that effect — a reporting proportion, not an incidence rate and not evidence the drug caused it. Wording is matched across sources by our own clinical vocabulary, so treat this as a prompt to pay attention, not a diagnosis.

Special populations

Arum in Pregnancy & Breastfeeding

Pregnancy And Lactation Likely Unsafe

When used orally because of its toxicity; 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

Everything else you take

See Every Supplement That Interacts With Orlistat

This page covers Arum only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Orlistat page lists 18 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Coffee Charcoal (moderate), European Mandrake (moderate), Fish Oil (moderate) and Glucomannan (moderate).

By severity: 1 major · 8 moderate · 9 minor.

From our pharmacist’s overview on the Orlistat page

“People who take Orlistat (Xenical, Alli) for weight loss often browse the very supplement aisle where fiber products and fish oil sit, and both show up on this page, so it deserves genuine attention before you mix anything in. Nearly all 18 ingredients on file can change how oral medications absorb from the gut, and the single major-ra…”

Reviewed by 2 · Jul 18, 2026

Open the Orlistat interaction page

How much people look this up

Where Arum and Orlistat 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 Arum
Top half

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

29 days ago today
Medication Orlistat
Top half

#896 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 Arum reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 20, 2026. The Arum and Orlistat 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 Arum

What is Arum?

Arum
  • Coughs and chest congestion
  • Sore throat
  • Promoting sweating (diaphoretic)
  • Skin and wart remedies (topical folk use)
  • Digestive complaints

Arum is a traditional European plant whose root has been used in folk medicine, but there is essentially no reliable human research to support any health benefit. The raw plant is toxic and irritating because of calcium oxalate crystals, so it should not be eaten or used casually. We do not recommend using Arum as a supplement, especially during pregnancy or breastfeeding.

Arum maculatum · Araceae · Root (tuber), and sometimes leaves · Dried root preparations, tinctures, and traditional folk remedies

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

Arum: dosing

There is no established or standardized safe dose for Arum. Because the plant is toxic and human research is lacking, no trustworthy dosing guidelines exist.We do not recommend taking Arum. If you encounter a product that contains it, do not use it without first checking with a pharmacist or doctor, and never prepare or eat the raw plant yourself.

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

Read the full Arum monograph & all interactions
Medication

About Orlistat

What Is Orlistat Used For?

Brand names: Xenical, Alli

Xenical and prescription-strength orlistat are approved to help obese adults lose weight and keep it off when used with a reduced-calorie diet. They are intended for people with a body mass index (BMI) of 30 or higher, or 27 or higher if other risk factors such as high blood pressure, diabetes, or dyslipidemia (abnormal cholesterol or fat levels in the blood) are present.

Alli is the over-the-counter version, approved for weight loss in overweight adults 18 and older when used with a reduced-calorie, low-fat diet and exercise program.

Most-Reported Side Effects for Orlistat

From FAERS, the FDA’s public side-effect reporting system (25,755 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Rectal discharge 2,434 reports
Gastrointestinal disorder 2,186 reports
Constipation 1,991 reports
Diarrhea 1,960 reports
Weight increased 1,944 reports
See full Orlistat drug information
Keep checking

Other Drugs & Arum

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

0Major
0Moderate
1Minor
2,828No known interaction
Minor

1 interaction

No interaction 2,828 drugs checked — show the list
Evidence & sources

Arum References

The 3 references that drive our Arum 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. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.
  2. Mrvos, R., Dean, B. S., and Krenzelok, E. P. Philodendron/dieffenbachia ingestions: are they a problem? J Toxicol Clin Toxicol 1991;29(4):485-491. PubMed
  3. Prakash Raju KNJ, Goel K, Anandhi D, Pandit VR, Surendar R, Sasikumar M. Wild tuber poisoning: Arum maculatum - A rare case report. Int J Crit Illn Inj Sci. 2018;8(2):111-114. 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 Arum and Orlistat Together: Common Questions

Is it safe to take Arum with Orlistat?
We do not list a known interaction between Arum and Orlistat. 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 Arum and Orlistat 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 Arum and Orlistat combination checked?
Interactions in our licensed database are recorded against drug classes. Orlistat is filed under 2 classifications, and Arum has documented interactions with 1 drug class — none of Orlistat'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 Arum interact with any other medications?
Yes. Arum has 1 documented drug interaction in our database — Orlistat 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 Orlistat interact with any supplements?
Yes. Orlistat has documented interactions with 18 supplements in our database — Arum is not one of them. The Orlistat interaction page linked on this page lists every one, ranked by severity.

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

Still Have a Question About Orlistat and Arum?

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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.