Drug & supplement interaction

Calamus + Aluminum Hydroxide

Aluminum Hydroxide brand names: Amphojel, Gaviscon, Alu-Cap.

Minor Interaction
Medically reviewed by · Updated September 2026
The bottom line Minor

Calamus has a minor interaction with Aluminum Hydroxide. Theoretically, taking calamus might reduce the effectiveness of antacids.

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

Calamus and Aluminum Hydroxide

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

Minor

ANTACIDS

Why this applies to Aluminum Hydroxide

Aluminum Hydroxide falls under ANTACIDS — the group Calamus interacts with.

Theoretically, taking calamus might reduce the effectiveness of antacids.
Some research suggests that calamus lowers gastric pH.
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 basic idea with these two. Aluminum hydroxide is an antacid, so its whole job is to neutralize stomach acid and ease that burning, sour-stomach feeling. There is some early lab-type research hinting that calamus may actually lower the pH in your stomach, meaning more acid. If that holds true in people, calamus could work against your antacid and make it feel like it isn't calming things down as well.

I want to be honest, though: this is rated as a minor, theoretical interaction based on weak, anecdotal evidence, so it's nothing to lose sleep over. The bigger concern is calamus itself, which contains beta-asarone and is best avoided. If you're considering it, please run it by your pharmacist or doctor first.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. 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

Calamus Also Interacts With Other Medications

Calamus has 1,098 moderate, 18 minor known drug interactions in our database — the Aluminum Hydroxide one above is one of them. If you take anything else, check it against the full list below.

Moderate 1,098 Minor 18 No known interaction 1,714 (incl. Aluminum Hydroxide)
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.

From our Q&A

Questions About Calamus or Aluminum Hydroxide

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

This page covers Calamus only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Aluminum Hydroxide page lists 35 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Calcium (moderate), Cinchona (moderate), Coffee Charcoal (moderate) and European Mandrake (moderate).

By severity: 1 major · 14 moderate · 20 minor.

From our pharmacist’s overview on the Aluminum Hydroxide page

“An antacid sounds harmless, and that is exactly why the supplement interactions with aluminum hydroxide (Amphojel, Gaviscon) deserve real attention before you combine it with much of anything. The most serious entry is activated charcoal, which can soak up many medications in the gut and sharply cut how much of them your body actually…”

Reviewed by 2 · Jul 18, 2026

Open the Aluminum Hydroxide 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 Aluminum Hydroxide 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 Aluminum Hydroxide 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
Steady interest

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

29 days ago today
Medication Aluminum Hydroxide
Top 5%

#125 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
Medication

About Aluminum Hydroxide

What Is Aluminum Hydroxide Used For?

Brand names: Amphojel, Gaviscon, Alu-Cap

Aluminum hydroxide is used in two distinct ways depending on the product. The oral liquid form relieves heartburn, acid indigestion, and sour stomach.

ProCure DryDrox, a topical ointment, is used on the skin to dry the oozing and weeping caused by poison ivy, oak, and sumac reactions.

See full Aluminum Hydroxide drug information
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
1,098Moderate
18Minor
1,713No known interaction
1,098 Moderate 18 Minor 1,713 No interaction
Moderate

1,098 interactions

Showing 60 of 1,098 moderate interactions — see all 1,098 on the Calamus page.

Minor

18 interactions

No interaction 1,713 drugs checked — show the list

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

Showing the 60 most looked-up of 1,713 medications checked with no known interaction — see the full Calamus list.

See the full Calamus interactions page
See every supplement checked against Aluminum Hydroxide, ranked by severity
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
Calamus monograph › Uses, safety, and every drug interaction in one place Aluminum Hydroxide supplement interactions › Every supplement checked against Aluminum Hydroxide, ranked by severity Aluminum Hydroxide drug information › The full plain-English guide to this medication Supplement interaction checker › Check any supplement or product against your medications Browse medications A–Z › Every drug we've checked against herbs & supplements Ask a pharmacist › Free, personal answer from our licensed team
Pharmacist Counseling Corner

Taking Calamus and Aluminum Hydroxide Together: Common Questions

Can you take Calamus with Aluminum Hydroxide?
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 Calamus and Aluminum Hydroxide 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 Aluminum Hydroxide and Calamus?

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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.