Drug & supplement interaction

Gum Arabic + Macitentan

Macitentan brand name: Opsumit.

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

Gum Arabic has a moderate interaction with Macitentan. Theoretically, gum arabic can alter the absorption of oral drugs due to its fiber content.

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

Gum Arabic and Macitentan

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

Moderate

ORAL DRUGS

Why this applies to Macitentan

Macitentan falls under ORAL DRUGS — the group Gum Arabic interacts with.

Theoretically, gum arabic can alter the absorption of oral drugs due to its fiber content.
Gum arabic has been used as a suspending osmotic agent in drug formulations. It might improve bioavailability of water-insoluble drugs like naproxen, but reduce absorption of polar drugs like amoxicillin. To avoid changes in absorption, take gum arabic 30-60 minutes after oral medications.
Severity Moderate Likelihood Possible Evidence B

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 simple version: gum arabic is mostly soluble fiber, and fiber sitting in your stomach and gut can sometimes grab onto a pill and change how much of it gets absorbed. With Macitentan (Opsumit), the worry is that taking the two close together could slightly lower how much medicine your body soaks up, which in theory might make it work a little less well for your lung blood pressure.

I want to be honest, though: this is mostly a theoretical concern based on weak evidence, not solid proof that it happens with Macitentan specifically. Macitentan is not a prodrug, so we're only talking about absorption here. To stay safe, a common tip is to take your Macitentan first and wait 30 to 60 minutes before the gum arabic. Please run this by your pharmacist or doctor before changing anything, since PAH medicine is important to keep steady.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Eltayeb IB, Awad AI, Elderbi MA, Shadad SA. Effect of gum arabic on the absorption of a single oral dose of amoxicillin in healthy Sudanese volunteers. J Antimicrob Chemother 2004;54:577-8. PubMed
  2. Beneke CE, Viljoen AM, Hamman JH. Polymeric plant-derived excipients in drug delivery. Molecules. 2009;14(7):2602-20. 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

Gum Arabic Also Interacts With Other Medications

Gum Arabic has 2,021 moderate known drug interactions in our database — the Macitentan one above is one of them. If you take anything else, check it against the full list below.

Moderate 2,021 No known interaction 809 (incl. Macitentan)
Taking anything else?

Check Another of Your Medications Against Gum Arabic

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

Everything else you take

See Every Supplement That Interacts With Macitentan

This page covers Gum Arabic only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Macitentan page lists 253 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), American Hellebore (major), American Mistletoe (major), Beer (major) and Grapefruit (major).

By severity: 9 major · 205 moderate · 39 minor.

From our pharmacist’s overview on the Macitentan page

“If you take macitentan (Opsumit) for pulmonary arterial hypertension, study this page rather than skim it. It lists 253 supplement and herbal ingredients, nine rated major.”

Reviewed by 2 · Jul 18, 2026

Open the Macitentan interaction page

One more smart check

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

We hold 3 real supplement products containing Gum Arabic, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Gum Arabic. Your product may carry other ingredients that interact with Macitentan too, on top of Gum Arabic — 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 Gum Arabic and Macitentan 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 Gum Arabic
Top half

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

29 days ago today
Medication Macitentan
Top 25%

#328 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 Gum Arabic

What is Gum Arabic?

Gum Arabic
  • Digestive and gut health
  • Source of soluble fiber
  • Constipation or bowel regularity
  • Prebiotic support
  • Cholesterol support
  • Blood sugar support

Gum arabic is a soluble dietary fiber from the acacia tree that is widely used as a safe food additive and is sometimes taken as a supplement for digestive health and as a prebiotic. Early studies suggest possible benefits for gut bacteria, cholesterol, and blood sugar, but the evidence is limited, and high doses can cause gas and bloating. Talk to your pharmacist or doctor before using it as a supplement.

Read the full Gum Arabic monograph & all interactions
Medication

About Macitentan

What Is Macitentan Used For?

Brand name: Opsumit

Macitentan tablets — sold under the brand name Opsumit — are used to treat pulmonary arterial hypertension (PAH, WHO Group I), a serious condition where the blood pressure in the arteries supplying the lungs is abnormally high. The goal is to slow down how quickly the disease gets worse and to lower the chances of being hospitalized because of it.

In clinical studies, it was shown to be effective in adults with mostly moderate-to-severe PAH symptoms. Patients in those studies had PAH caused by unknown or inherited reasons, connective tissue disorders, or congenital heart disease with repaired heart shunts.

See full Macitentan drug information
Keep checking

Other Drugs & Gum Arabic

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

0Major
2,021Moderate
0Minor
808No known interaction
2,021 Moderate 808 No interaction
Moderate

2,021 interactions

Showing 60 of 2,021 moderate interactions — see all 2,021 on the Gum Arabic page.

No interaction 808 drugs checked — show the list

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

Showing the 60 most looked-up of 808 medications checked with no known interaction — see the full Gum Arabic list.

See the full Gum Arabic interactions page
See every supplement checked against Macitentan, 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
Gum Arabic monograph › Uses, safety, and every drug interaction in one place Macitentan supplement interactions › Every supplement checked against Macitentan, ranked by severity Macitentan 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 Gum Arabic and Macitentan Together: Common Questions

Can you take Gum Arabic with Macitentan?
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.
How serious is the Gum Arabic and Macitentan 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 Macitentan and Gum Arabic?

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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.