Drug & supplement interaction

Black Seed + Siponimod

Siponimod brand name: Mayzent.

Moderate Interaction
The bottom line Moderate

Siponimod falls into 2 drug categories that Black Seed can interact with; the most serious is rated moderate. Theoretically, black seed might interfere with immunosuppressive therapy.

Read the full interaction report
SeverityModerate
LikelihoodPossible
Interactions2
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Black Seed and Siponimod

These two interact in 2 distinct ways. Each one is explained separately below.

Why Are There 2 Interactions?

Black Seed interacts with whole categories of medication. Siponimod falls into 2 of those categories, so it can interact with Black Seed in 2 different ways. We’ve listed each one below — your overall risk is driven by the most serious of them (Moderate).

Moderate

IMMUNOSUPPRESSANTS

1 of 2

Why this applies to Siponimod

Siponimod falls under IMMUNOSUPPRESSANTS — the group Black Seed interacts with.

Theoretically, black seed might interfere with immunosuppressive therapy.
Animal and in vitro studies suggest that black seed might stimulate immune function. However, other animal studies suggest that black seed may suppress immune function.
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: siponimod (Mayzent) works by calming down part of your immune system to protect your nerves in MS. Black seed is a bit of a wild card here. In lab dishes and animal studies, some research suggests it might rev the immune system up, while other studies suggest it might dial it down. So in theory it could either tug against siponimod's job or pile on top of it.

I want to be honest about how thin this evidence is, though. This concern comes only from test-tube and animal work, not from people, so we really don't know if it matters in real life. Food-amount sprinkles of black seed are unlikely to be a problem, but concentrated supplement doses are less studied. Before adding a black seed supplement, please check with your neurologist or pharmacist first.

References
  1. Islam, S. N., Begum, P., Ahsan, T., Huque, S., and Ahsan, M. Immunosuppressive and cytotoxic properties of Nigella sativa. Phytother.Res. 2004;18(5):395-398.
  2. Fararh, K. M., Atoji, Y., Shimizu, Y., Shiina, T., Nikami, H., and Takewaki, T. Mechanisms of the hypoglycaemic and immunopotentiating effects of Nigella sativa L. oil in streptozotocin-induced diabetic hamsters. Res Vet.Sci 2004;77(2):123-129. PubMed
  3. El Obeid, A., Al Harbi, S., Al Jomah, N., and Hassib, A. Herbal melanin modulates tumor necrosis factor alpha (TNF-alpha), interleukin 6 (IL-6) and vascular endothelial growth factor (VEGF) production. Phytomedicine. 2006;13(5):324-333.
  4. Abbas, A. T., Abdel-Aziz, M. M., Zalata, K. R., and Tel, Abd Al-Galel. Effect of dexamethasone and Nigella sativa on peripheral blood eosinophil count, IgG1 and IgG2a, cytokine profiles and lung inflammation in murine model of allergic asthma. Egypt J Im
  5. Massadeh, A. M., Al Safi, S. A., Momani, I. F., Al Mahmoud, M., and Alkofahi, A. S. Analysis of cadmium and lead in mice organs: effect of Nigella sativa L. (Black Cumin) on the distribution and immunosuppressive effect of cadmium-lead mixture in mice. B PubMed
Moderate

CYTOCHROME P450 2C9 (CYP2C9) SUBSTRATES

2 of 2

Siponimod also falls under CYTOCHROME P450 2C9 (CYP2C9) SUBSTRATES.

Theoretically, black seed might increase levels of drugs metabolized by CYP2C9.
In vitro research suggests that thymoquinone, a constituent of black seed, can decrease the metabolism of phenytoin by a mechanism possibly related to the inhibition of CYP2C9. The effect of black seed on CYP2C9 is unclear. This has not been shown in humans.
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 gist with Mayzent (siponimod) and black seed. Your body relies on a liver enzyme called CYP2C9 to clear siponimod out of your system. Black seed contains thymoquinone, and in test-tube studies it seemed to slow that same enzyme down. If that held true in people, siponimod could build up a bit more than expected, which might mean more side effects like a slower heart rate, headache, dizziness, higher blood pressure, or changes in your liver tests.

I want to be honest, though: this is only a theoretical concern based on lab work, not anything proven in humans, and the real effect of black seed on this enzyme is unclear. Food-amount use is unlikely to matter, but before adding a concentrated supplement, please run it by your pharmacist or neurologist.

References
  1. Wang Z, Wang X, Wang Z, et al. Potential herb-drug interaction risk of thymoquinone and phenytoin. Chem Biol Interact. 2022;353:109801. 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

Black Seed Also Interacts With Other Medications

Black Seed has 911 moderate 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.

Taking anything else?

Check Another of Your Medications Against Black Seed

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

From our Q&A

Questions About Black Seed 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 Black Seed 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 Black Seed 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 Black Seed as Part of a Dietary Supplement Product? Check It for Interactions

We hold 226 real supplement products containing Black Seed, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Black Seed. Your product may carry other ingredients that interact with Siponimod too, on top of Black Seed — 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 Black Seed 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 Black Seed
Top 25%

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

29 days ago today
Medication Siponimod
Steady interest

#2,528 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 Black Seed

What is Black Seed?

Black Seed
  • Respiratory support (asthma, allergies, cough)
  • Digestive upset
  • Immune support
  • Blood sugar and cholesterol support
  • General inflammation

Black seed (Nigella sativa) is a traditional spice and remedy that has been studied for asthma, blood sugar, cholesterol, and blood pressure, with early research showing some promise but no firmly proven benefits. It is generally well tolerated in food amounts, but supplement-strength doses are less studied, so talk to your pharmacist or doctor before using it—especially if you are pregnant, breastfeeding, or take other medicines.

Read the full Black Seed 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 & Black Seed

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

0Major
911Moderate
0Minor
1,918No known interaction
Moderate

911 interactions

Showing 60 of 911 moderate interactions — see all 911 on the Black Seed page.

No interaction 1,918 drugs checked — show the list
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

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Pharmacist Counseling Corner

Taking Black Seed and Siponimod Together: Common Questions

Can you take Black Seed 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 2 interactions listed for Black Seed and Siponimod?
Siponimod belongs to more than one drug category, and Black Seed 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 Black Seed 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 Black Seed?

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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.