Drug & supplement interaction

Gamma-oryzanol + Macitentan

Macitentan brand name: Opsumit.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Gamma-oryzanol and Macitentan 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.

Know someone taking this? Share
Interaction report

Gamma-oryzanol and Macitentan

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 Macitentan and Gamma-oryzanol 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.

Worth understanding: our licensed dataset holds no drug-interaction record for Gamma-oryzanol at all — not against Macitentan, and not against any other medication we track. This verdict therefore rests on the absence of any recorded data, not on research that looked at this combination and found nothing. We cannot rule an interaction out.

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.

Gamma-oryzanol safety at a glance

Gamma-oryzanol overall Use caution Generally well tolerated in studies, but long-term safety is not well established.
Pregnancy Avoid Not enough safety information, so it is best avoided during pregnancy.
Breastfeeding Avoid No reliable safety data, so avoid while breastfeeding.

Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Macitentan and Gamma-oryzanol? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
What to actually watch for

What Macitentan’s Own FDA Label Lists

This is not an interaction — none of it involves Gamma-oryzanol. These are the most notable effects listed in the ADVERSE REACTIONS section of Macitentan’s own FDA label, for the medication by itself. Knowing the drug’s own list makes it easier to work out the likely cause if something new turns up while you take both. 6 of them are worth acting on rather than waiting out — marked below.

  • Heart failure Worth acting on
  • Anemia Worth acting on
  • A severe allergic reaction Worth acting on
  • A higher chance of infection Worth acting on mentioned in 6.6% of FDA reports for Macitentan
  • Liver problems Worth acting on
  • An allergic reaction Worth acting on
  • Flushing
  • A stuffy or runny nose
  • Sore throat
  • Low blood pressure

Showing the 10 most notable of 14 label-listed effects — ranked by how unusual each one is across medicines generally, with serious effects weighted up.

From the ADVERSE REACTIONS section of the FDA label for Macitentan. Read the label on DailyMed › Where a percentage is shown, it is the share of 68,860 voluntary FDA FAERS reports for Macitentan that mention that effect — a reporting proportion, not an incidence rate and not evidence the drug caused it. Gamma-oryzanol’s licensed record lists no adverse effects our clinical vocabulary could match, so there is no Gamma-oryzanol side to compare — that is a limit of the record, not a statement that Gamma-oryzanol has no side effects.

Overlapping uses

What Macitentan Is Prescribed For, and What Gamma-oryzanol Has Been Studied For

These two come up together because they touch the same health topic — not because they do the same job. Macitentan is a prescription medicine with approved uses on its FDA label. Gamma-oryzanol is a supplement: what follows is what researchers have looked at it for, and how strong that evidence is.

Macitentan is prescribed for: Macitentan tablets — sold under the brand name Opsumit — are used to treat pulmonary arterial hypertension (PAH, WHO Group I), a type of high blood pressure in the arteries of the lungs. The goal is to slow the disease from getting worse and to lower the chance of being hospitalized because of PAH. In the key clinical study, macitentan was used in adults with mainly moderate-to-severe PAH symptoms. Patients had PAH caused by unknown or inherited causes, connective tissue disorders, or congenital heart disease with repaired shunts.

Gamma-oryzanol has been studied for:

  • Hypertension studied, not established Gamma-oryzanol has been studied for this. Natural Medicines rates the evidence: Insufficient Reliable Evidence To Rate Read what the research shows

    Gamma-oryzanol for hypertension

    Oral gamma-oryzanol has only been evaluated in combination with sesame oil; its benefits when used alone are unclear.

Effectiveness ratings and the research summaries above are the verbatim record from the Natural Medicines database, which grades evidence from “Effective” down to “Insufficient Reliable Evidence To Rate”. A rating below the top of that scale means researchers have looked at it — not that it works, and never that it can stand in for a prescribed medicine. Do not stop or replace Macitentan on your own; if you are taking Gamma-oryzanol for the same health topic, tell your prescriber, especially if the medicine is being adjusted to a target.

Everything else you take

See Every Supplement That Interacts With Macitentan

This page covers Gamma-oryzanol 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 Gamma-oryzanol as Part of a Dietary Supplement Product? Check It for Interactions

We hold 272 real supplement products containing Gamma-oryzanol, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Gamma-oryzanol. Even though Gamma-oryzanol itself has no known interaction with Macitentan, another ingredient on your label might. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Gamma-oryzanol 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 Gamma-oryzanol
Top half

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

29 days ago today
Medication Macitentan
Top 25%

#598 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.
  • Freshness: we automatically re-check this combination every week — this pair was last verified October 4, 2026. The Gamma-oryzanol and Macitentan records this page draws on were last updated June 22, 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 Gamma-oryzanol

What is Gamma-oryzanol?

  • High cholesterol
  • Menopausal symptoms
  • Athletic performance and muscle building
  • Mild anxiety
  • Skin protection (topical)

Gamma-oryzanol is a mix of plant compounds taken from rice bran oil, used mainly for cholesterol, menopause symptoms, and as a sports supplement. The evidence is limited and mostly comes from small or older studies, so benefits are not well proven. It appears generally well tolerated, but talk with your pharmacist or doctor before using it.

Poaceae · Rice bran oil (derived from Oryza sativa bran) · Capsules, tablets, powder, topical creams

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

Gamma-oryzanol: dosing

There is no official or standardized dose for gamma-oryzanol. Doses used in research have varied widely, and what works for one use may not apply to another.The best approach is to follow the directions on the product label and not take more than recommended.

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

Read the full Gamma-oryzanol 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 type of high blood pressure in the arteries of the lungs. The goal is to slow the disease from getting worse and to lower the chance of being hospitalized because of PAH.

In the key clinical study, macitentan was used in adults with mainly moderate-to-severe PAH symptoms. Patients had PAH caused by unknown or inherited causes, connective tissue disorders, or congenital heart disease with repaired shunts.

Most-Reported Side Effects for Macitentan

From FAERS, the FDA’s public side-effect reporting system (68,860 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Dyspnea 11,958 reports
Headache 8,323 reports
Diarrhea 6,584 reports
Nausea 5,972 reports
Fatigue 5,041 reports
See full Macitentan drug information
Keep checking

Other Drugs & Gamma-oryzanol

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

0Major
0Moderate
0Minor
2,829No known interaction
No interaction 2,829 drugs checked — show the list
Sources

Sources & How We Checked

We checked Gamma-oryzanol against Macitentan in the Natural Medicines interaction database and found no documented interaction on file. The medication overview comes from MedlinePlus, and supplement label details from the NIH Dietary Supplement Label Database.

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 Gamma-oryzanol and Macitentan Together: Common Questions

Is it safe to take Gamma-oryzanol with Macitentan?
We do not list a known interaction between Gamma-oryzanol and Macitentan. 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.
Are Gamma-oryzanol and Macitentan used for the same thing?
They overlap in purpose, which usually means the real question is whether you need both rather than whether they are safe together. This page lists the shared uses and how strong the evidence is for Gamma-oryzanol in each. That is a conversation for your prescriber, especially if Macitentan is being adjusted to a target.
Does Macitentan interact with any supplements?
Yes. Macitentan has documented interactions with 253 supplements in our database — Gamma-oryzanol is not one of them. The Macitentan 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 Macitentan and Gamma-oryzanol?

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.