Drug & supplement interaction

Coconut Water + Macitentan

Macitentan brand name: Opsumit.

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

Coconut Water has a moderate interaction with Macitentan. Theoretically, taking coconut water with antihypertensive drugs might increase the risk of hypotension.

Read the full interaction report
SeverityModerate
LikelihoodPossible
EvidenceD
What do Severity, Likelihood & Evidence mean?
Know someone taking this? Share
Facebook Post Reddit Email
On this page
Interaction report

Coconut Water and Macitentan

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

Moderate

ANTIHYPERTENSIVE DRUGS

Why this applies to Macitentan

Macitentan falls under ANTIHYPERTENSIVE DRUGS — the group Coconut Water interacts with.

Theoretically, taking coconut water with antihypertensive drugs might increase the risk of hypotension.
Preliminary clinical research shows that drinking coconut water might lower systolic and diastolic blood pressure in patients with hypertension.
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 simple version. Macitentan (Opsumit) already works to relax and open up your blood vessels to ease pressure in the lung arteries, and a side effect of that can be lower blood pressure overall. Coconut water, in some early studies, seems to nudge blood pressure down a little too. Put the two together and there's a theoretical chance your blood pressure could dip more than expected.

I want to be honest, this concern is based on pharmacology and small studies, not strong proof. An occasional glass with a meal is unlikely to cause trouble for most folks. But if you drink large amounts daily and notice dizziness, lightheadedness, or feeling faint, mention it to your pharmacist or doctor before changing anything.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Alleyne T, Roache S, Thomas C, Shirley A. The control of hypertension by use of coconut water and mauby: two tropical food drinks. West Indian Med J 2005;54:3-8. 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

Coconut Water Also Interacts With Other Medications

Coconut Water has 192 moderate, 86 minor 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 192 Minor 86 No known interaction 2,552 (incl. Macitentan)
Taking anything else?

Check Another of Your Medications Against Coconut Water

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

From our Q&A

Questions About Coconut Water or Macitentan

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

This page covers Coconut Water 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 Coconut Water as Part of a Dietary Supplement Product? Check It for Interactions

We hold 67 real supplement products containing Coconut Water, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Coconut Water. Your product may carry other ingredients that interact with Macitentan too, on top of Coconut Water — 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 Coconut Water 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 Coconut Water
Top half

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

29 days ago today
Medication Macitentan
Top 5%

#89 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 Coconut Water

What is Coconut Water?

Coconut Water
  • Hydration
  • Rehydration after exercise
  • Electrolyte replacement
  • General wellness drink
  • Blood pressure support

Coconut water is a natural drink rich in potassium and other electrolytes that many people use for hydration, especially around exercise. For most healthy people it is a safe, tasty beverage, but it is not a proven medicine and should not replace medical electrolyte solutions for serious dehydration. People with kidney disease or those on potassium-affecting medicines should check with their pharmacist or doctor first.

Read the full Coconut Water 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 & Coconut Water

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

0Major
192Moderate
86Minor
2,551No known interaction
192 Moderate 86 Minor 2,551 No interaction
Moderate

192 interactions

Showing 60 of 192 moderate interactions — see all 192 on the Coconut Water page.

Minor

86 interactions

Showing 60 of 86 minor interactions — see all 86 on the Coconut Water page.

No interaction 2,551 drugs checked — show the list

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

Showing the 60 most looked-up of 2,551 medications checked with no known interaction — see the full Coconut Water list.

See the full Coconut Water 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
Coconut Water 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 Coconut Water and Macitentan Together: Common Questions

Can you take Coconut Water 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 Coconut Water 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 Coconut Water?

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.