Drug & supplement interaction

Rhodiola + Riociguat

Riociguat brand name: Adempas.

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

Riociguat falls into 3 drug categories that Rhodiola can interact with; the most serious is rated moderate. Theoretically, taking rhodiola with antihypertensive drugs might increase the risk of hypotension.

Read the full interaction report
SeverityModerate
LikelihoodPossible
Interactions3
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Rhodiola and Riociguat

These two interact in 3 distinct ways. Each one is explained separately below.

Why Are There 3 Interactions?

Rhodiola interacts with whole categories of medication. Riociguat falls into 3 of those categories, so it can interact with Rhodiola in 3 different ways. We’ve listed each one below — your overall risk is driven by the most serious of them (Moderate).

Moderate

ANTIHYPERTENSIVE DRUGS

1 of 3

Why this applies to Riociguat

Riociguat falls under ANTIHYPERTENSIVE DRUGS — the group Rhodiola interacts with.

Theoretically, taking rhodiola with antihypertensive drugs might increase the risk of hypotension.
In vitro and animal research shows that rhodiola extract inhibits angiotensin-converting enzyme (ACE) and might lower blood pressure.
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 thing to keep in mind: Riociguat (Adempas) works by relaxing and widening your blood vessels, which already lowers blood pressure. Rhodiola, based on lab and animal studies, may also have a mild blood pressure lowering effect. Put the two together and there's a chance your blood pressure could drop more than expected.

If that happens, you might feel dizzy, lightheaded, faint, or notice headaches, especially when you stand up quickly. I want to be honest though: this concern comes from test tube and animal research only, not from people, so it's more theoretical than proven. Since Riociguat is already carefully dosed for blood pressure, I'd just run the idea of adding Rhodiola past your doctor or pharmacist first.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Kwon YI, Jang HD, Shetty K. Evaluation of Rhodiola crenulata and Rhodiola rosea for management of type II diabetes and hypertension. Asia Pac J Clin Nutr 2006;15:425-32.
  2. Apostolidis E, Kwon YI, Shetty K. Potential of cranberry-based herbal synergies for diabetes and hypertension management. Asia Pac J Clin Nutr 2006;15:433-41.
Moderate

P-GLYCOPROTEIN SUBSTRATES

2 of 3

Riociguat also falls under P-GLYCOPROTEIN SUBSTRATES.

Theoretically, rhodiola might increase levels of P-glycoprotein substrates.
In vitro research shows that rhodiola inhibits P-glycoprotein. Theoretically, using rhodiola with P-glycoprotein substrates might increase drug levels and potentially increase the risk of adverse effects.
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: your body uses a kind of cellular bouncer called P-glycoprotein to move certain drugs around and out. Riociguat is one of the medicines that bouncer handles. In lab dish studies, rhodiola seemed to slow that bouncer down. In theory, that could let a bit more riociguat hang around in your body than usual.

Why that matters: riociguat already lowers blood pressure, so higher levels could nudge you toward dizziness, lightheadedness, headache, an upset stomach, or feeling faint, especially when standing up. I want to be honest though, this is only based on test-tube research, not real people, so it's a theoretical concern, not a proven problem. Since riociguat is a sensitive drug, please check with your pharmacist or doctor before adding rhodiola.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Hellum BH, Tosse A, Hoybakk K, et al. Potent in vitro inhibition of CYP3A4 and P-glycoprotein by Rhodiola rosea. Planta Med 2010;76:331-8.
Minor

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES

3 of 3

Riociguat also falls under CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES.

Theoretically, rhodiola might increase levels of drugs metabolized by CYP3A4.
In vitro research shows that rhodiola inhibits CYP3A4. This effect is highly variable and appears to be dependent on the rhodiola product studied. However, a clinical study in healthy young males found that taking rhodiola extract 290 mg daily for 14 days does not inhibit the metabolism of midazolam, a CYP3A4 substrate.
Severity Minor 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

Your body clears riociguat (Adempas) using a liver enzyme called CYP3A4. In a test tube, rhodiola can slow that enzyme down, and in theory that could let more riociguat build up in your system. Since riociguat works by relaxing blood vessels, higher levels could nudge your blood pressure too low, which might show up as dizziness, lightheadedness, headache, or feeling faint.

Here's the reassuring part: this is mostly lab-dish data, and the effect varies a lot between rhodiola products. A real-world study in healthy men found rhodiola did not meaningfully change how a similar CYP3A4 drug was cleared. So the risk looks small and uncertain. Still, because riociguat affects blood pressure, check with your pharmacist or doctor before pairing them.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Hellum BH, Tosse A, Hoybakk K, et al. Potent in vitro inhibition of CYP3A4 and P-glycoprotein by Rhodiola rosea. Planta Med 2010;76:331-8.
  2. Thu OK, Nilsen OG, Hellum B. In vitro inhibition of cytochrome P-450 activities and quantification of constituents in a selection of commercial Rhodiola rosea products. Pharm Bio. 2016 Dec;54(12):3249-3256.
  3. Thu OK, Spigset O, Nilsen OG, Hellum B. Effect of commercial Rhodiola rosea on CYP enzyme activity in humans. Eur J Clin Pharmacol. 2016 Mar;72(3):295-300. 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

Rhodiola Also Interacts With Other Medications

Rhodiola has 623 moderate, 647 minor known drug interactions in our database — the Riociguat one above is among them. If you take anything else, check it against the full list below.

Moderate 623 Minor 647 No known interaction 1,560 (incl. Riociguat)
Taking anything else?

Check Another of Your Medications Against Rhodiola

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

From our Q&A

Questions About Rhodiola or Riociguat

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

This page covers Rhodiola only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Riociguat page lists 230 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), Grapefruit (major) and St. John's Wort (major).

By severity: 6 major · 187 moderate · 37 minor.

From our pharmacist’s overview on the Riociguat page

“Riociguat (Adempas) works by relaxing the blood vessels in your lungs, which also lowers blood pressure, so I read this list of 230 supplements and herbs with real concern, and the six rated major are what to understand first. Grapefruit can push riociguat levels up and intensify its effect, while St.”

Reviewed by 2 · Jul 18, 2026

Open the Riociguat interaction page

One more smart check

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

We hold 2,713 real supplement products containing Rhodiola, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Rhodiola. Your product may carry other ingredients that interact with Riociguat too, on top of Rhodiola — 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 Rhodiola and Riociguat 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 Rhodiola
Top 5%

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

29 days ago today
Medication Riociguat
Steady interest

#1,640 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 Rhodiola

What is Rhodiola?

Rhodiola
  • Fatigue and low energy
  • Stress and coping (adaptogen)
  • Mental performance and focus
  • Mild depression
  • Physical and exercise performance

Rhodiola is an herb traditionally used to fight fatigue and help the body cope with stress. Some small studies suggest it may modestly reduce fatigue and improve mood, but the evidence is limited and not strong. It is generally well tolerated for short-term use, but talk to your pharmacist or doctor before trying it, and avoid it during pregnancy and breastfeeding.

Read the full Rhodiola monograph & all interactions
Medication

About Riociguat

What Is Riociguat Used For?

Brand name: Adempas

Riociguat tablets — sold under the brand names Adempas and Riociguat — are approved for adults with two types of high blood pressure in the lungs. The first is chronic thromboembolic pulmonary hypertension (CTEPH), a condition caused by blood clots that have blocked or narrowed the arteries in the lungs. Riociguat is used when surgery has not fully fixed the problem, or when surgery is not an option.

The second is pulmonary arterial hypertension (PAH), a progressive disease where the arteries in the lungs become stiff and narrowed. In PAH, riociguat helps improve exercise ability, functional class (how well you can get around day-to-day), and slows disease worsening. It can be used alone or combined with other PAH medicines called endothelin receptor antagonists or prostanoids.

See full Riociguat drug information
Keep checking

Other Drugs & Rhodiola

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

0Major
623Moderate
647Minor
1,559No known interaction
623 Moderate 647 Minor 1,559 No interaction
Moderate

623 interactions

Showing 60 of 623 moderate interactions — see all 623 on the Rhodiola page.

Minor

647 interactions

Showing 60 of 647 minor interactions — see all 647 on the Rhodiola page.

No interaction 1,559 drugs checked — show the list

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

Showing the 60 most looked-up of 1,559 medications checked with no known interaction — see the full Rhodiola list.

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

Can you take Rhodiola with Riociguat?
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 3 interactions listed for Rhodiola and Riociguat?
Riociguat belongs to more than one drug category, and Rhodiola 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 Rhodiola and Riociguat 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 Riociguat and Rhodiola?

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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.