Drug & supplement interaction

Marshmallow + Megestrol Acetate

Megestrol Acetate brand names: Megestrol, Megace.

Minor Interaction
The bottom line Minor

Marshmallow has a minor interaction with Megestrol Acetate. Theoretically, mucilage in marshmallow might impair absorption of oral drugs.

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

Marshmallow and Megestrol Acetate

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

Minor

ORAL DRUGS

Why this applies to Megestrol Acetate

Megestrol Acetate falls under ORAL DRUGS — the group Marshmallow interacts with.

Theoretically, mucilage in marshmallow might impair absorption of oral drugs.
Marshmallow contains mucilage which can affect oral drug absorption. To avoid changes in absorption, take marshmallow 30-60 minutes after oral medications.
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 with megestrol and marshmallow root. Marshmallow is loaded with mucilage, a slippery gel-like fiber. The concern is that this gel could coat your stomach and gut and grab onto your megestrol as it passes through, so a little less of the medicine gets absorbed. With megestrol, that could mean a slightly weaker effect, less of the appetite boost and weight gain you may be counting on, or reduced support of its hormone-related effects.

I want to be honest, though: this is a theoretical concern based on how mucilage behaves, not something proven in studies. The simple fix is spacing them out, taking marshmallow about 30 to 60 minutes after your megestrol. When in doubt, run it by your pharmacist or doctor first.

References
  1. Monographs on the medicinal uses of plant drugs. Exeter, UK: European Scientific Co-op Phytother, 1997.
  2. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
  3. McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
  4. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.

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

Marshmallow Also Interacts With Other Medications

Marshmallow has 1 moderate, 2,038 minor known drug interactions in our database — the Megestrol Acetate 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 Marshmallow

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

Everything else you take

See Every Supplement That Interacts With Megestrol Acetate

This page covers Marshmallow only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Megestrol Acetate 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), Glucomannan (moderate) and Guar Gum (moderate).

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

From our pharmacist’s overview on the Megestrol Acetate page

“Megestrol acetate (Megace) is usually prescribed to restore appetite and weight in people who are seriously ill, so the drug only helps if it actually gets absorbed. That is exactly where this list earns real caution.”

Reviewed by 2 · Jul 18, 2026

Open the Megestrol Acetate interaction page

One more smart check

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

We hold 1,622 real supplement products containing Marshmallow, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Marshmallow. Your product may carry other ingredients that interact with Megestrol Acetate too, on top of Marshmallow — 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 Marshmallow and Megestrol Acetate 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 Marshmallow
Top 10%

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

29 days ago today
Medication Megestrol Acetate
Top half

#792 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 Marshmallow

What is Marshmallow?

Marshmallow
  • Cough and sore throat
  • Dry mouth and throat irritation
  • Digestive upset and heartburn
  • Skin irritation
  • Soothing inflamed tissue

Marshmallow root is a traditional herb rich in soothing, gel-like fibers called mucilage, which is why it has long been used for coughs, sore throats, and stomach irritation. Evidence for these uses is mostly traditional and preliminary, but it is generally considered gentle and well-tolerated for short-term use. As with any supplement, check with your pharmacist or doctor before using it, especially if you are pregnant, breastfeeding, or taking other medicines.

Read the full Marshmallow monograph & all interactions
Medication

About Megestrol

What Is Megestrol Used For?

Brand names: Megestrol, Megace

Megestrol acetate is used for two distinct purposes depending on the formulation. Megestrol Acetate oral suspension is indicated for treating anorexia (loss of appetite), cachexia (severe weight loss and muscle wasting), or unexplained significant weight loss in patients with a diagnosis of AIDS.

Megestrol Acetate tablets are used for the palliative treatment — meaning to ease symptoms, not cure — of advanced breast cancer or endometrial (uterine lining) cancer that is recurrent, inoperable, or has spread to other parts of the body. Tablets are not a replacement for surgery, radiation, or chemotherapy.

See full Megestrol drug information
Keep checking

Other Drugs & Marshmallow

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

0Major
1Moderate
2,038Minor
790No known interaction
Moderate

1 interaction

Minor

2,038 interactions

Showing 60 of 2,038 minor interactions — see all 2,038 on the Marshmallow page.

No interaction 790 drugs checked — show the list

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

Showing the 60 most looked-up of 790 medications checked with no known interaction — see the full Marshmallow 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 Marshmallow and Megestrol Acetate Together: Common Questions

Can you take Marshmallow with Megestrol Acetate?
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 Marshmallow and Megestrol Acetate 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 Megestrol Acetate and Marshmallow?

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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.