Drug & supplement interaction

Danshen + Entacapone

Entacapone brand name: Comtan.

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

Danshen has a moderate interaction with Entacapone. Theoretically, danshen might affect the levels and clinical effects of drugs requiring glucuronidation.

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

Danshen and Entacapone

Here is the interaction we found between these two, with the evidence behind it.

Moderate

GLUCURONIDATED DRUGS

Why this applies to Entacapone

Entacapone falls under GLUCURONIDATED DRUGS — the group Danshen interacts with.

Theoretically, danshen might affect the levels and clinical effects of drugs requiring glucuronidation.
In vitro research shows that danshen induces the expression of glucuronosyltransferases. However, it also inhibits the activity of glucuronosyltransferases, including various members of the 1A and 2B families. The extent of inhibition of a specific glucuronosyltransferase seems to be dependent on whether or not the danshen is processed via 'sweating'. This type of processing may affect the levels of constituents in danshen that alter glucuronosyltransferase activity. 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 gist for your Parkinson's regimen: Entacapone is mostly cleared from your body through a process called glucuronidation. Danshen, in test-tube and animal studies, seems to tug on those same clearing enzymes in both directions, sometimes speeding them up and sometimes slowing them down. So the theory is that Danshen could shift how much entacapone stays in your system, but honestly, which way it would go isn't clear, and it has never actually been reported in real people.

If entacapone levels nudged upward, you might notice more of its usual effects, like extra dyskinesia (involuntary movements), nausea, diarrhea, or harmless reddish-brown urine. If levels dropped, your levodopa might wear off sooner. This is weak, theoretical evidence, so I wouldn't lose sleep over it. Still, please run Danshen past your pharmacist or neurologist before adding it.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Liu J, Shi Y, Wu C, et al. Comparison of sweated and non-sweated ethanol extracts of Salvia miltiorrhiza Bge. (Danshen) effects on human and rat hepatic UDP-glucuronosyltransferase and preclinic herb-drug interaction potential evaluation. Curr Drug Metab

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 123 major, 935 moderate known drug interactions in our database — the Entacapone one above is one of them. If you take anything else, check it against the full list below.

Major 123 Moderate 935 No known interaction 1,772 (incl. Entacapone)
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 Entacapone

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 Entacapone, 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 Entacapone

This page covers Danshen only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Entacapone page lists 33 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Ayahuasca (moderate), Black Horehound (moderate), Breadfruit (moderate) and Brussels Sprout (moderate).

By severity: 1 major · 22 moderate · 10 minor.

Open the Entacapone 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 Entacapone 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 Entacapone 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

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

29 days ago today
Medication Entacapone
Steady interest

#2,324 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 Entacapone

What Is Entacapone Used For?

Brand name: Comtan

Entacapone tablets are used as an add-on therapy — always taken together with levodopa and carbidopa — to treat end-of-dose 'wearing-off' in people with Parkinson's disease. 'Wearing-off' is when the benefit of a levodopa dose fades before the next dose is due, causing symptoms like stiffness or slowness to return.

Entacapone has no effect on Parkinson's disease on its own; it only works when combined with levodopa and carbidopa. Its effectiveness has not been thoroughly studied in people with Parkinson's disease who do not experience wearing-off.

See full Entacapone 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.

123Major
935Moderate
0Minor
1,771No known interaction
123 Major 935 Moderate 1,771 No interaction
Major

123 interactions

Showing 60 of 123 major interactions — see all 123 on the Danshen page.

Moderate

935 interactions

Showing 60 of 935 moderate interactions — see all 935 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 Entacapone, 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 Entacapone supplement interactions › Every supplement checked against Entacapone, ranked by severity Entacapone 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 Entacapone Together: Common Questions

Can you take Danshen with Entacapone?
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.
How serious is the Danshen and Entacapone 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 Entacapone 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.