Drug & supplement interaction

Rhodiola + Siponimod

Siponimod brand name: Mayzent.

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

Siponimod falls into 3 drug categories that Rhodiola can interact with; the most serious is rated moderate. Theoretically, rhodiola might increase levels of drugs metabolized by CYP2C9.

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

Rhodiola and Siponimod

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. Siponimod 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

CYTOCHROME P450 2C9 (CYP2C9) SUBSTRATES

1 of 3

Why this applies to Siponimod

Siponimod falls under CYTOCHROME P450 2C9 (CYP2C9) SUBSTRATES — the group Rhodiola interacts with.

Theoretically, rhodiola might increase levels of drugs metabolized by CYP2C9.
In vitro research shows that rhodiola inhibits CYP2C9. This effect is highly variable and appears to be dependent on the rhodiola product studied. Also, a clinical study in healthy young males found that taking rhodiola extract 290 mg daily for 14 days reduces the metabolism of losartan, a CYP2C9 substrate, by 21% after 4 hours.
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 situation with these two together. Your body clears siponimod in large part through a liver enzyme called CYP2C9. Rhodiola may gently slow that same enzyme down. If it does, siponimod could clear a little more slowly and build up in your system, which can mean stronger effects and a higher chance of side effects like a slow heart rate, headache, dizziness, higher blood pressure, or changes in liver tests.

I want to be honest about the evidence though: this is mostly theoretical and lab-based, with one small human study showing only a modest (about 21%) slowdown for a similar drug. Siponimod is already carefully dosed based on your genetics, so even small shifts deserve attention. Please don't start or stop anything on your own. Just check with your pharmacist or MS doctor first.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. 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.
  2. 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
  3. Woron J, Siwek M. Unwanted effects of psychotropic drug interactions with medicinal products and diet supplements containing plant extracts. Psychiatr Pol 2018;52(6):983-96. PubMed
Moderate

IMMUNOSUPPRESSANTS

2 of 3

Siponimod also falls under IMMUNOSUPPRESSANTS.

Theoretically, rhodiola use might interfere with immunosuppressive therapy.
In vitro and animal research show that rhodiola has immunostimulatory 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 idea behind this pairing. Siponimod works by quieting down certain immune cells so they cause less nerve damage in MS. Rhodiola, on the other hand, has shown immune-stimulating effects in lab and animal studies. So in theory, rhodiola could push the immune system in the opposite direction and partly work against what siponimod is trying to do, which could mean less control over your MS over time.

I want to be honest about the strength of this, though. This is based only on test tube and animal research, not on real people taking both together, so it's a theoretical concern rather than something we've clearly seen happen. Still, with an MS medication that's this important, I'd loop in your neurologist or pharmacist before adding rhodiola.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Skopriska-Rozewska E, Wojcik R, Siwicki AK, et al. The effect of Rhodiola quadrifida extracts on cellular immunity in mice and rats. Pol J Vet Sci 2008;11:105-11.
  2. Mishra KP, Chanda S, Shukla K, Ganju L. Adjuvant effect of aqueous extract of Rhodiola imbricate rhizome on the immune responses to tetanus toxoid and ovalbumin in rats. Immunopharmacol Immunotoxicol 2010;32:141-6.
  3. Li HX, Sze SC, Tong Y, Ng TB. Production of Th1- and Th2-dependent cytokines induced by the Chinese medicine herb, Rhodiola algida, on human peripheral blood monocytes. J Ethnopharmacol 2009;123:257-66. PubMed
  4. Mishra KP, Ganju L, Chanda S, et al. Aqueous extract of Rhodiola imbricate rhizome stimulates Toll-like receptor 4, granzyme-B and Th1 cytokines in vitro. Immunobiology 2009;214:27-31.
Minor

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES

3 of 3

Siponimod 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

Here's the short version: your body partly clears Siponimod using a liver enzyme called CYP3A4. In lab dishes, Rhodiola can mildly block that same enzyme. In theory, that could let Siponimod build up a bit, which might mean more of its usual effects, like a slower heart rate (especially when you first start it), headache, or a stronger drop in your infection-fighting white blood cells.

That said, I wouldn't lose sleep over this one. The signal comes from test-tube work and is very inconsistent, and a human study actually found Rhodiola did not slow down another CYP3A4 drug. So a real-world problem seems unlikely. Still, Siponimod is a serious medicine with careful dosing, so check with your pharmacist or doctor before adding Rhodiola rather than starting or stopping anything on your own.

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 Siponimod 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. Siponimod)
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 Siponimod

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 Siponimod, 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 Siponimod

This page covers Rhodiola only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Siponimod page lists 190 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Grapefruit (major), St. John's Wort (major), Acacia Rigidula (moderate) and Active Hexose Correlated Compound (ahcc) (moderate).

By severity: 3 major · 147 moderate · 40 minor.

From our pharmacist’s overview on the Siponimod page

“Siponimod (Mayzent) treats secondary progressive multiple sclerosis, and because its blood level depends heavily on two liver enzymes, this is a supplement list to respect. Most of these entries can nudge siponimod levels up or down; the three rated major are grapefruit, which raises them, St.”

Reviewed by 2 · Jul 18, 2026

Open the Siponimod 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 Siponimod 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 Siponimod 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 Siponimod
Steady interest

#2,485 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 Siponimod

What Is Siponimod Used For?

Brand name: Mayzent

Mayzent (siponimod) is approved for adults with relapsing forms of multiple sclerosis (MS). This includes three specific types: clinically isolated syndrome (a first episode of MS-like symptoms), relapsing-remitting MS (periods of attacks followed by recovery), and active secondary progressive MS (a phase where the disease gradually worsens but still has active relapses).

It is taken by mouth once daily and is intended as a long-term treatment to reduce relapses and slow disease progression.

See full Siponimod 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 Siponimod, 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 Siponimod supplement interactions › Every supplement checked against Siponimod, ranked by severity Siponimod 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 Siponimod Together: Common Questions

Can you take Rhodiola with Siponimod?
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 Siponimod?
Siponimod 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 Siponimod 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 Siponimod 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.