Drug & supplement interaction

Danshen + Warfarin

Warfarin brand name: Warfarin.

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

Warfarin falls into 5 drug categories that Danshen can interact with; the most serious is rated major. Theoretically, danshen may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.

Read the full interaction report
SeverityMajor
LikelihoodProbable
Interactions5
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Danshen and Warfarin

These two interact in 5 distinct ways. Each one is explained separately below.

Why Are There 5 Interactions?

Danshen interacts with whole categories of medication. Warfarin falls into 5 of those categories, so it can interact with Danshen in 5 different ways. We’ve listed each one below — your overall risk is driven by the most serious of them (Major).

Major

ANTICOAGULANT/ANTIPLATELET DRUGS

1 of 5

Why this applies to Warfarin

Warfarin falls under ANTICOAGULANT/ANTIPLATELET DRUGS — the group Danshen interacts with.

Theoretically, danshen may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Danshen has been reported to have antithrombotic effects. Animal research also suggests that taking a danshen combination formula with clopidogrel exhibits a synergistic increase in antiplatelet aggregation and prolongation of coagulation time when compared with either taken alone.
Severity Major Likelihood Probable Evidence D

Interaction 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..

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

Here's the concern with pairing Danshen and warfarin: both can thin your blood, just in different ways. Warfarin lowers your blood's clotting ability, and Danshen seems to have its own blood-thinning and antiplatelet effects. Stack them together and you may get more thinning than intended. There are also case reports of Danshen raising the INR (the lab number that tracks how thin your blood is), which can push you into the danger zone for bleeding.

That matters because warfarin is a narrow-margin drug, so even small shifts can bring on easy bruising, nosebleeds, bleeding gums, or more serious internal bleeding. The evidence here is mostly anecdotal and theoretical, but with a drug like warfarin I'd play it safe. Please check with your pharmacist or doctor before adding Danshen.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Heck AM, DeWitt BA, Lukes AL. Potential interactions between alternative therapies and warfarin. Am J Health Syst Pharm 2000;57:1221-7. DOI
  2. Yin QS, Chen L, Mi RH, Ai H, Yin JJ, Liu XJ, Wei XD. Efficacy and safety of danshen compound tablets in preventing thalidomide-associated thromboembolism in patients with multiple myeloma: a multicenter retrospective study. Med Sci Monit. 2016 Oct 20;22:3 PubMed
  3. Zheng D, Zhang W, Hou M, et al. Evaluation of herb-drug interactions between compound Danshen dripping pills and clopidogrel based on the pharmacokinetics and pharmacodynamics in rats. Biomed Chromatogr. 2023;37(9):e5684. PubMed
Moderate

CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES

2 of 5

Warfarin also falls under CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES.

Theoretically, danshen may increase the levels and clinical effects of drugs metabolized by CYP1A2.
In vitro research shows that danshen tincture and various constituents of danshen inhibit the activity of CYP1A2. However, this activity has not been shown in humans when theophylline, a CYP1A2 substrate, was used as a target drug.
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 pairing Danshen with warfarin: there are really two concerns. The one on file is a lab-based idea that Danshen may slow down a liver enzyme (CYP1A2) that helps clear warfarin. In theory, that could let warfarin build up and thin your blood more than intended, raising the chance of bruising, nosebleeds, or more serious bleeding. But honestly, this part is only seen in test-tube studies and hasn't held up in people, so I wouldn't lose sleep over the enzyme angle alone.

What worries me more is that Danshen itself can affect blood clotting, and warfarin is a narrow-margin drug where small shifts matter. Please don't start or stop anything on your own. Loop in your pharmacist or doctor so your INR can be watched closely.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Wang X, Cheung CM, Lee WY, Or PM, Yeung JH. Major tanshinones of Danshen (Salvia miltiorrhiza) exhibit different modes of inhibition on human CYP1A2, CYP2C9, CYP2E1 and CYP3A4 activities in vitro. Phytomedicine. 2010 Sep;17(11):868-75. PubMed
  2. Wang X, Yeung JH. Investigation of cytochrome P450 1A2 and 3A inhibitory properties of Danshen tincture. Phytomedicine. 2012 Feb 15;19(3-4):348-54. PubMed
  3. Zhou X, Chan K, Yeung JH. Herb-drug interactions with Danshen (Salvia miltiorrhiza): a review on the role of cytochrome P450 enzymes. Drug Metabol Drug Interact. 2012 Mar 2;27(1):9-18.
Moderate

CYTOCHROME P450 2C9 (CYP2C9) SUBSTRATES

3 of 5

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

Theoretically, danshen may increase the levels and clinical effects of drugs metabolized by CYP2C9.
In vitro research shows that various constituents of danshen inhibit the activity of CYP2C9. So far, this interaction has not been reported 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 thing with Danshen and warfarin: your body clears warfarin partly through a liver enzyme called CYP2C9, and lab studies suggest Danshen may slow that enzyme down. If warfarin breaks down more slowly, it can build up and thin your blood more than intended. That raises your risk of bruising, nosebleeds, bleeding gums, or more serious bleeding. On top of that, Danshen itself may affect clotting, so the two together could add up.

Now, I want to be honest about the evidence. This effect has only been seen in test-tube and animal studies, not in actual people. But warfarin is a narrow-margin medicine where small shifts matter, so I wouldn't combine these without looping in your doctor or pharmacist first. They may want to check your INR.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Wang X, Cheung CM, Lee WY, Or PM, Yeung JH. Major tanshinones of Danshen (Salvia miltiorrhiza) exhibit different modes of inhibition on human CYP1A2, CYP2C9, CYP2E1 and CYP3A4 activities in vitro. Phytomedicine. 2010 Sep;17(11):868-75. PubMed
Moderate

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES

4 of 5

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

Danshen might alter the levels and clinical effects of drugs metabolized by CYP3A4.
Preliminary clinical research in healthy males shows that the administration of danshen for 10-14 days induces intestinal CYP3A4 and increases the clearance of midazolam, a CYP3A4 substrate. The maximum concentration of midazolam was decreased by 31% to 67%, and drug levels were decreased by 27% to 80%. However, a single dose of danshen has the opposite effect, increasing maximum concentrations of midazolam by 87%.
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 thing with Danshen and warfarin: there are really two concerns stacked together. The mechanism on file is about CYP3A4, an enzyme that helps break down many drugs. Taken for a couple of weeks, Danshen seems to speed that enzyme up, which could lower warfarin levels slightly. But warfarin's effect doesn't depend much on CYP3A4, so this metabolic piece is fairly minor on its own.

The bigger worry is that Danshen itself may thin the blood. Stacked on top of warfarin, that can push you toward too much blood thinning, meaning easy bruising, nosebleeds, or more serious bleeding. Because warfarin is a narrow therapeutic index drug, even small shifts matter and your INR can swing. Please don't add Danshen without checking with your pharmacist or doctor first.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Qiu F, Wang G, Zhang R, Sun J, et al. Effect of danshen extract on the activity of CYP3A4 in healthy volunteers. Br J Clin Pharmacol 2010;69:656-62. PubMed
  2. Qiu F, Jiang J, Ma Y, Wang G, Gao C, Zhang X, Zhang L, Liu S, He M, Zhu L, Ye Y, Li Q, Miao P. Opposite Effects of Single-Dose and Multidose Administration of the Ethanol Extract of Danshen on CYP3A in Healthy Volunteers. Evid Based Complement Alternat Me PubMed
Moderate

WARFARIN (Coumadin)

5 of 5
Theoretically, danshen may increase the risk of bleeding if used with warfarin.
There have been several case reports of increased international normalized ratio (INR) after concomitant use of danshen and warfarin. Elevations in INR have occurred as early as 3-5 days after start of danshen. However, a clinical trial in adults taking warfarin with stable INR found that the addition of compound danshen dripping pills, containing danshen extract, Panax notoginseng, and borneol, 270 mg three times daily for 4 weeks did not alter INR levels or the average required warfarin dose when compared to baseline. These findings are consistent with animal research, which found no change in warfarin pharmacokinetics with the use of danshen. Other research in healthy adult males also shows that taking a combination of danshen and kudzu with warfarin does not increases plasma warfarin area under the curve, but may reduce plasma soluble thrombomodulin levels. However, other research shows that danshen might increase the rate of absorption and decrease the elimination rate of warfarin. Also, research in healthy adult males shows that taking a combination of danshen and kudzu with warfarin increases plasma area under the curve of danshensu, a constituent of danshen, by approximately 29.5-fold. Danshen should be used cautiously in patients taking warfarin.
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 bottom line if you take warfarin and you're thinking about Danshen. Warfarin is a blood thinner with a very narrow safety window, meaning small shifts can tip you from "just right" toward too much thinning. Danshen seems to act on the same side of that balance, and there are real-world case reports of people's INR climbing within just 3 to 5 days of starting it. A higher INR means your blood is thinner than intended, which can show up as easy bruising, nosebleeds, bleeding gums, blood in urine or stool, or harder-to-stop cuts.

To be fair, the evidence is mixed. One trial of a Danshen-containing pill didn't change INR at all, so this isn't a guaranteed problem. But because warfarin is so finicky, I'd never have you start or stop Danshen on your own. Please run it by your pharmacist or doctor first so they can watch your INR closely.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Yu CM, Chan JC, Sanderson JE. Chinese herbs and warfarin potentiation by danshen. J Intern Med 1997;241:337-9. PubMed
  2. Tam LS, et al. Warfarin interacions with Chinese traditional medicines: danshen and methyl salicylate medicated oil. Aust N Z J Med 1995;25:258.
  3. Chan TY. Interaction between warfarin and danshen (Salvia miltiorrhiza). Ann Pharmacother 2001;35:501-4. DOI
  4. Chan TY. Drug interactions as a cause of overanticoagulation and bleedings in Chinese patients receiving warfarin. Int J Clin Pharmacol Ther 1998;36:403-5.
  5. Izzat MB, Yim APC, El-Zufari MH. A taste of Chinese medicine! Ann Thorac Surg 1998;66:941-2. PubMed
  6. Heck AM, DeWitt BA, Lukes AL. Potential interactions between alternative therapies and warfarin. Am J Health Syst Pharm 2000;57:1221-7. DOI
  7. Chu Y, Zhang L, Wang XY, Guo JH, Guo ZX, Ma XH. The effect of Compound Danshen Dripping Pills, a Chinese herb medicine, on the pharmacokinetics and pharmacodynamics of warfarin in rats. J Ethnopharmacol. 2011 Oct 11;137(3):1457-61. PubMed
  8. Zhang Z, Ge B, Zhou L, Lam TN, Zuo Z. Induction of liver cytochrome P450s by Danshen-Gegen formula is the leading cause for its pharmacokinetic interactions with warfarin. J Ethnopharmacol. 2014 Jul 3;154(3):672-86. PubMed
  9. Zhou X, Chan K, Yeung JH. Herb-drug interactions with Danshen (Salvia miltiorrhiza): a review on the role of cytochrome P450 enzymes. Drug Metabol Drug Interact. 2012 Mar 2;27(1):9-18.
  10. Zhou L, Wang S, Zhang Z, Lau BS, Fung KP, Leung PC, Zuo Z. Pharmacokinetic and pharmacodynamic interaction of Danshen-Gegen extract with warfarin and aspirin. J Ethnopharmacol. 2012 Sep 28;143(2):648-55. PubMed
  11. Lv C, Liu C, Yao Z, et al. The clinical pharmacokinetics and pharmacodynamics of warfarin when combined with compound danshen: a case study for combined treatment of coronary heart diseases with atrial fibrillation. Front Pharmacol. 2017 Nov 21;8:826. PubMed
  12. Zhang Y, Yang M, Ho NJ, et al. Is it safe to take Radix Salvia Miltiorrhiza - Radix Pueraria Lobate product with warfarin and aspirin? A pilot study in healthy human subjects. J Ethnopharmacol. 2020 Nov 15;262:113151. 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

Danshen Also Interacts With Other Medications

Danshen has 122 major, 936 moderate known drug interactions in our database — the Warfarin one above is among them. If you take anything else, check it against the full list below.

Major 122 Moderate 936 No known interaction 1,772 (incl. Warfarin)
Taking anything else?

Check Another of Your Medications Against Danshen

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

From our Q&A

Questions About Danshen or Warfarin

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

This page covers Danshen only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Warfarin page lists 361 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Alfalfa (major), American Ginseng (major), Beer (major) and Cannabis (major).

By severity: 16 major · 301 moderate · 44 minor.

From our pharmacist’s overview on the Warfarin page

“People take warfarin to prevent dangerous clots, and many are the same people reaching for glucosamine for sore joints or a multivitamin containing vitamin K, which makes this a list that deserves genuine respect. Of the 361 supplements on file for warfarin, 16 carry a major rating, and the danger runs in both directions: some add to w…”

Reviewed by 2 · Jul 18, 2026

Open the Warfarin interaction page

One more smart check

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

We hold 18 real supplement products containing Danshen, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Danshen. Your product may carry other ingredients that interact with Warfarin too, on top of Danshen — 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 Danshen and Warfarin 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 Danshen
Top half

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

29 days ago today
Medication Warfarin
Top 10

#5 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 Danshen

What is Danshen?

Danshen
  • Heart and circulation support
  • Angina (chest pain)
  • High blood pressure
  • Anxiety and stress
  • Liver health

Danshen is a root used in traditional Chinese medicine, mainly for heart and circulation problems. Some early research is promising, but the evidence is not strong enough to confirm it works for any condition, and it may affect blood clotting. Talk to a pharmacist or doctor before using it, especially if you take other medicines or have a health condition.

Read the full Danshen monograph & all interactions
Medication

About Warfarin

What Is Warfarin Used For?

Brand name: Warfarin

Warfarin sodium tablets and Jantoven tablets are both used to prevent and treat venous thrombosis (blood clots in the veins) and pulmonary embolism (a clot in the lungs). They are also used to prevent clot-related complications in people with atrial fibrillation (an irregular heart rhythm) or who have had a heart valve replaced.

In people who have had a heart attack, warfarin is used to reduce the risk of death, another heart attack, stroke, or other clotting events. It does not dissolve an existing clot, but it helps prevent the clot from growing and stops new dangerous clots from forming.

See full Warfarin drug information
Keep checking

Other Drugs & Danshen

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

122Major
936Moderate
0Minor
1,771No known interaction
122 Major 936 Moderate 1,771 No interaction
Major

122 interactions

Showing 60 of 122 major interactions — see all 122 on the Danshen page.

Moderate

936 interactions

Showing 60 of 936 moderate interactions — see all 936 on the Danshen page.

No interaction 1,771 drugs checked — show the list

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

Showing the 60 most looked-up of 1,771 medications checked with no known interaction — see the full Danshen list.

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

Can you take Danshen with Warfarin?
This is rated a major interaction, so the combination is best avoided unless your doctor or pharmacist has specifically told you otherwise. Read the full details on this page and confirm with your pharmacist before combining them.
Why are there 5 interactions listed for Danshen and Warfarin?
Warfarin belongs to more than one drug category, and Danshen 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 Danshen and Warfarin interaction?
We rate it Major. This is a clinically significant combination that is generally best avoided, or used only under the direct supervision of your physician or pharmacist.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

Still Have a Question About Warfarin and Danshen?

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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.