Drug & supplement interaction

Black Seed + Clopidogrel

Clopidogrel brand name: Plavix.

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

Clopidogrel falls into 3 drug categories that Black Seed can interact with; the most serious is rated moderate. Theoretically, black seed may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.

Read the full interaction report
SeverityModerate
LikelihoodPossible
Interactions3
EvidenceD
What do Severity, Likelihood & Evidence mean?
Know someone taking this? Share
Facebook Post Reddit Email
On this page
Interaction report

Black Seed and Clopidogrel

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

Why Are There 3 Interactions?

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

Moderate

ANTICOAGULANT/ANTIPLATELET DRUGS

1 of 3

Why this applies to Clopidogrel

Clopidogrel falls under ANTICOAGULANT/ANTIPLATELET DRUGS — the group Black Seed interacts with.

Theoretically, black seed may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
In vitro and animal research suggests that black seed extract can inhibit platelet aggregation and clotting, and increase bleeding time. In addition, decreased platelet counts have occurred in a human case report and in animal research.
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 about clopidogrel (Plavix): its whole job is to make your blood platelets less sticky so they don't clump and form dangerous clots. Black seed seems to do something similar. In lab and animal studies, it has slowed platelet clumping, lengthened bleeding time, and in a couple of reports even lowered platelet counts.

So the worry is overlap. If black seed adds to what Plavix is already doing, you could bruise more easily or be slower to stop bleeding from a small cut. Watch for things like nosebleeds, bleeding gums, blood in your urine or stool, or unusually dark bruises. I want to be honest though: this is theoretical and based mostly on lab and animal work, not strong human studies. Food amounts of black seed are unlikely to matter. Before adding a concentrated supplement, check with your pharmacist or doctor.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Enomoto, S., Asano, R., Iwahori, Y., Narui, T., Okada, Y., Singab, A. N., and Okuyama, T. Hematological studies on black cumin oil from the seeds of Nigella sativa L. Biol.Pharm.Bull 2001;24(3):307-310. PubMed
  2. Al Jishi, S. A. and Abuo, Hozaifa B. Effect of Nigella sativa on blood hemostatic function in rats. J Ethnopharmacol. 2003;85(1):7-14. PubMed
  3. Awad, E. M. and Binder, B. R. In vitro induction of endothelial cell fibrinolytic alterations by Nigella sativa. Phytomedicine 2005;12(3):194-202. PubMed
  4. Wang X, Jiang A, Batra V. Severe thrombocytopenia associated with black seed oil and evening primrose oil. Cureus. 2020;12(6):e8390. PubMed
  5. Alkharfy K, Jan B, Alotaibi K, et al. Clopidogrel-herb Interactions: A Pharmacokinetic and Pharmacodynamic Assessment in a Rat Model. Curr Drug Metab 2021;22(12):969-977. PubMed
Moderate

CYTOCHROME P450 2C9 (CYP2C9) SUBSTRATES

2 of 3

Clopidogrel 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 a wrinkle that matters for Plavix (clopidogrel): it's a prodrug, meaning it starts out inactive and your liver enzymes have to switch it on before it can thin your blood and protect against clots. So the usual rule (an enzyme blocker makes a drug build up and act stronger) actually flips here. If black seed slows down the enzymes that activate clopidogrel, you could end up with less clot protection, not more.

That said, this concern is purely theoretical. It comes from lab dish studies on a different drug (phenytoin) and the effect on clopidogrel hasn't been shown in real people. Cooking-amount black seed is unlikely to matter, but concentrated supplements are less studied. Since clopidogrel guards against stroke and heart attack, please run any black seed supplement by your pharmacist or doctor first.

Contact Dr. Brian directly if you have additional questions on this interaction
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
Moderate

CLOPIDOGREL (Plavix)

3 of 3
Theoretically, black seed may increase the risk of bleeding if used with clopidogrel.
Animal research shows that taking black seed extract daily for 2 weeks prior to a single dose of clopidogrel increases maximum concentrations of clopidogrel by approximately 31% and modestly decreases oral clearance. Furthermore, bleeding time was increased by 12%. 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 short version on pairing black seed with clopidogrel (Plavix). Clopidogrel is a blood thinner that keeps your platelets from clumping into clots, which is exactly why your doctor gave it after a stent, heart attack, or stroke. The concern here is that black seed could nudge its effect up a bit, meaning slightly more bleeding risk. Think easy bruising, nosebleeds, bleeding gums, or cuts that take longer to stop.

I want to keep this in perspective though. The only evidence we have is from animal studies, where higher drug levels and a small (about 12%) increase in bleeding time showed up. This has never been confirmed in people. A sprinkle of the spice in food is unlikely to matter, but concentrated supplements are a different story. Before adding black seed capsules or oil, please check with your pharmacist or doctor.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Alkharfy K, Jan B, Alotaibi K, et al. Clopidogrel-herb Interactions: A Pharmacokinetic and Pharmacodynamic Assessment in a Rat Model. Curr Drug Metab 2021;22(12):969-977. 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 Clopidogrel one above is among them. If you take anything else, check it against the full list below.

Moderate 911 No known interaction 1,919 (incl. Clopidogrel)
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 Clopidogrel

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 Clopidogrel, 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 Clopidogrel

This page covers Black Seed only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Clopidogrel page lists 309 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Danshen (major), Grapefruit (major), Piracetam (major) and St. John's Wort (major).

By severity: 5 major · 258 moderate · 46 minor.

From our pharmacist’s overview on the Clopidogrel page

“Clopidogrel (Plavix) keeps platelets from sticking together after a stent, heart attack, or stroke, which makes this a list to take carefully. Of the 309 supplements and herbs on file, 202 carry blood-thinning or antiplatelet activity of their own and can stack bleeding risk on top of the drug's, while most of the rest change how the l…”

Reviewed by 2 · Jul 18, 2026

Open the Clopidogrel 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 Clopidogrel 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 Clopidogrel 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%

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

29 days ago today
Medication Clopidogrel
Top 1%

#12 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 Clopidogrel

What Is Clopidogrel Used For?

Brand name: Plavix

Clopidogrel tablets are used to reduce the risk of heart attack and stroke in people with acute coronary syndrome (ACS) — including unstable angina and non-ST-elevation or ST-elevation heart attacks — and in people with a history of recent heart attack, recent stroke, or established peripheral arterial disease. For ACS, it is typically given alongside aspirin.

It works by preventing platelets (blood cells that trigger clotting) from clumping together, which helps keep arteries open and lowers the chance of a dangerous clot forming.

See full Clopidogrel 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
911 Moderate 1,918 No 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

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

Showing the 60 most looked-up of 1,918 medications checked with no known interaction — see the full Black Seed list.

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

Can you take Black Seed with Clopidogrel?
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 Black Seed and Clopidogrel?
Clopidogrel 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 Clopidogrel 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 Clopidogrel and Black Seed?

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.