Drug & supplement interaction

Calamus + Edrophonium, Atropine

Edrophonium, Atropine brand name: Enlon-Plus.

Moderate Interaction
The bottom line Moderate

Edrophonium, Atropine falls into 2 drug categories that Calamus can interact with; the most serious is rated moderate. Theoretically, concurrent use of anticholinergic drugs and calamus might decrease the effectiveness of the anticholinergic drug.

Read the full interaction report
SeverityModerate
LikelihoodPossible
Interactions2
EvidenceD
What do Severity, Likelihood & Evidence mean?
Know someone taking this? Share
Interaction report

Calamus and Edrophonium, Atropine

These two interact in 2 distinct ways. Each one is explained separately below.

Why Are There 2 Interactions?

Calamus interacts with whole categories of medication. Edrophonium, Atropine falls into 2 of those categories, so it can interact with Calamus in 2 different ways. We’ve listed each one below — your overall risk is driven by the most serious of them (Moderate).

Moderate

ANTICHOLINERGIC DRUGS

1 of 2

Why this applies to Edrophonium, Atropine

Edrophonium, Atropine falls under ANTICHOLINERGIC DRUGS — the group Calamus interacts with.

Theoretically, concurrent use of anticholinergic drugs and calamus might decrease the effectiveness of the anticholinergic drug.
In vitro evidence shows that calamus can inhibit acetylcholinesterase (AChE).
Severity Moderate 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 idea behind this one. Enlon-Plus is a combination shot used in hospital settings, and the atropine part works by blocking acetylcholine, a chemical messenger in your body. Calamus seems to do the opposite in lab tests: it blocks the enzyme that normally clears acetylcholine away, so more of it can hang around. In theory, that could push back against atropine and make it work a little less well, which might mean things like a slower heart rate or more saliva and stomach activity than expected.

I want to be honest about the strength of this, though. It comes only from test-tube and animal research, not real patients, so it's more of a 'good to know' than a red flag. Since this medicine is given by professionals during procedures, just let your care team know about any supplements you use.

References
  1. Oh, M. H., Houghton, P. J., Whang, W. K., and Cho, J. H. Screening of Korean herbal medicines used to improve cognitive function for anti-cholinesterase activity. Phytomedicine 2004;11(6):544-548. PubMed
Moderate

CHOLINERGIC DRUGS

2 of 2

Edrophonium, Atropine also falls under CHOLINERGIC DRUGS.

Theoretically, concurrent use of cholinergic drugs and calamus might have an additive effect and increase the risk of cholinergic effects.
In vitro evidence shows that calamus can inhibit acetylcholinesterase (AChE).
Severity Moderate 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 idea behind this pairing. Enlon-Plus combines edrophonium, which boosts a body chemical called acetylcholine by blocking the enzyme that breaks it down (acetylcholinesterase), with atropine, which is added to soften the cholinergic side effects. In lab studies, calamus appears to block that same enzyme. So in theory, adding calamus could pile on top of edrophonium's action and push the cholinergic effects higher, meaning things like excess saliva and drooling, watery eyes, stomach cramping, slow heart rate, or muscle twitching.

I want to be honest about how thin this evidence is. It comes from test-tube and animal work, not real patients, so it's theoretical. On top of that, calamus carries its own safety concerns and is best avoided anyway. This is also a hospital-given drug, so just let your care team know about any supplements.

References
  1. Oh, M. H., Houghton, P. J., Whang, W. K., and Cho, J. H. Screening of Korean herbal medicines used to improve cognitive function for anti-cholinesterase activity. Phytomedicine 2004;11(6):544-548. 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

Calamus Also Interacts With Other Medications

Calamus has 1,097 moderate, 19 minor known drug interactions in our database — the Edrophonium, Atropine one above is among them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Calamus

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

Everything else you take

See Every Supplement That Interacts With Edrophonium, Atropine

This page covers Calamus only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Edrophonium, Atropine page lists 34 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Henbane (major), Scopolia (major), Angel's Trumpet (moderate), Arenaria Rubra (moderate) and Bacopa (moderate).

By severity: 2 major · 29 moderate · 3 minor.

From our pharmacist’s overview on the Edrophonium, Atropine page

“Enlon-Plus combines edrophonium, which raises levels of the nerve messenger acetylcholine, with atropine, which tempers its side effects, and the supplements listed below can tip that balance in either direction. I read this list with real caution.”

Reviewed by 2 · Jul 18, 2026

Open the Edrophonium, Atropine interaction page

One more smart check

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

We hold 71 real supplement products containing Calamus, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Calamus. Your product may carry other ingredients that interact with Edrophonium, Atropine too, on top of Calamus — 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 Calamus and Edrophonium, Atropine 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 Calamus
Top half

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

29 days ago today
Medication Edrophonium, Atropine
Top half

#773 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 Calamus

What is Calamus?

Calamus
  • Digestive upset and gas
  • Loss of appetite
  • Memory and focus (traditional)
  • Coughs and colds
  • Calming or sedative effect (traditional)

Calamus is a swamp plant with a long history in Ayurvedic and traditional Chinese medicine, mostly for digestive and nervous-system complaints. However, it contains beta-asarone, a compound linked to cancer and other toxic effects in animal studies, which is why the U.S. FDA banned it from foods. Because of these safety concerns and a lack of solid human evidence, it is generally best avoided.

Read the full Calamus monograph & all interactions
Keep checking

Other Drugs & Calamus

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

0Major
1,097Moderate
19Minor
1,713No known interaction
Moderate

1,097 interactions

Showing 60 of 1,097 moderate interactions — see all 1,097 on the Calamus page.

Minor

19 interactions

No interaction 1,713 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

Keep exploring
Pharmacist Counseling Corner

Taking Calamus and Edrophonium, Atropine Together: Common Questions

Can you take Calamus with Edrophonium, Atropine?
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.
Why are there 2 interactions listed for Calamus and Edrophonium, Atropine?
Edrophonium, Atropine belongs to more than one drug category, and Calamus interacts with each of those categories a little differently. We list every one so nothing is missed — your overall risk is driven by the most serious of them.
How serious is the Calamus and Edrophonium, Atropine 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 Edrophonium, Atropine and Calamus?

Our pharmacists answer your medication & supplement questions — free.

Ask a pharmacist

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.