Drug & supplement interaction

Cnidium + Tolcapone

Tolcapone brand name: Tasmar.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Cnidium and Tolcapone in our sources. Absence of a documented interaction is not the same as proven safety, and does not guarantee one does not exist. Do not start, stop, or change a medication or supplement based on this page; confirm with your pharmacist or doctor first.

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Interaction report

Cnidium and Tolcapone

We checked these two against our interaction database. Here is what we found.

No Known Interaction Found

We did not find a documented interaction between Tolcapone and Cnidium in our sources. This does not guarantee that the combination is completely free of risk — there is often limited research on supplements and herbal products, especially around drug interactions.

If you decide to take both, the practical routine is simple: add one new thing at a time and note the date you started it. If the combination is going to disagree with you, it usually shows in the first days to a couple of weeks — and a start date turns “I’ve been feeling off” into something a pharmacist can actually work with. Do not stop a prescribed medicine on your own.

Always talk with your pharmacist or doctor before making changes to your medications or supplements, particularly if you take several medications or have an ongoing health condition.

Cnidium safety at a glance

Cnidium overall Use caution Human safety data are limited, so use carefully and under professional guidance.
Pregnancy Avoid Not enough safety information is available, so it is best avoided during pregnancy.
Breastfeeding Avoid No reliable safety data exist, so avoid use while breastfeeding.

Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Tolcapone and Cnidium? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Tolcapone

Interactions in our licensed database are recorded against drug classes, not just single drug names. Tolcapone is filed under 3 classifications — dopamine agonists, hepatotoxic drugs, oral drugs. Cnidium has documented interactions with 2 drug classes — the most serious being anticoagulant/antiplatelet drugs (moderate) and cns depressants (moderate) — and none of Tolcapone’s classifications are among them.

Classification data comes from our licensed Natural Medicines dataset. A medication can belong to classes beyond those recorded there, so this describes how the check was run — it is not a safety guarantee.

Keep it in perspective

Cnidium Does Interact With Other Medications

Cnidium has 351 moderate known drug interactions in our database — Tolcapone isn’t one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Cnidium

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

What to actually watch for

What Tolcapone’s Own FDA Label Lists

This is not an interaction — none of it involves Cnidium. These are the most notable effects listed in the ADVERSE REACTIONS section of Tolcapone’s own FDA label, for the medication by itself. Knowing the drug’s own list makes it easier to work out the likely cause if something new turns up while you take both. 10 of them are worth acting on rather than waiting out — marked below.

  • A stroke or mini-stroke Worth acting on
  • Pain or burning when passing urine Worth acting on
  • Memory problems Worth acting on
  • Dehydration Worth acting on
  • Trouble swallowing Worth acting on
  • Bleeding in the gut Worth acting on
  • Trouble passing urine Worth acting on
  • A slow heartbeat Worth acting on
  • Blood clots Worth acting on
  • Hallucinations Worth acting on

Showing the 10 most notable of 69 label-listed effects — ranked by how unusual each one is across medicines generally, with serious effects weighted up.

From the ADVERSE REACTIONS section of the FDA label for Tolcapone. Read the label on DailyMed › Cnidium’s licensed record lists no adverse effects our clinical vocabulary could match, so there is no Cnidium side to compare — that is a limit of the record, not a statement that Cnidium has no side effects.

Everything else you take

See Every Supplement That Interacts With Tolcapone

This page covers Cnidium only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Tolcapone page lists 58 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Beer (major), Siberian Cocklebur (major), Wine (major) and Ashwagandha (moderate).

By severity: 4 major · 45 moderate · 9 minor.

Open the Tolcapone interaction page

One more smart check

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

We hold 175 real supplement products containing Cnidium, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Cnidium. Even though Cnidium itself has no known interaction with Tolcapone, another ingredient on your label might. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Cnidium and Tolcapone 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 Cnidium
Top half

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

29 days ago today
Medication Tolcapone
Steady interest

#1,983 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.

Where does our data come from?
  • Source: the Natural Medicines (TRC Healthcare) clinical database — the evidence-graded professional reference for herb & supplement interactions.
  • Citation library: 103,510 references behind our interaction content, 65,311 of them resolved to verified PubMed/DOI sources. See every Cnidium reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 20, 2026. The Cnidium and Tolcapone records this page draws on were last updated June 22, 2026.
  • What “no known interaction” means: no documented interaction in the sources above — not a guarantee of safety. Supplements are studied far less than prescription drugs, so we say exactly what the evidence supports, and nothing more.
Data structure & sourcing designed and verified by .
Supplement

About Cnidium

What is Cnidium?

Cnidium
  • Skin conditions and itching
  • Erectile dysfunction and low libido
  • Eczema and dermatitis
  • Antifungal or antimicrobial washes
  • Athletic performance
  • General antioxidant support

Cnidium is the dried fruit of an Asian plant long used in traditional Chinese medicine, mostly for skin problems and sexual health. Modern human evidence for these uses is very limited, with most research coming from laboratory and animal studies. Talk with your pharmacist or doctor before using it, and avoid it during pregnancy and breastfeeding.

Cnidium monnieri · Apiaceae (Umbelliferae) · Dried ripe fruit (seeds); sometimes the rhizome · Capsules, powdered extract, tinctures, topical creams and ointments, and as an ingredient in traditional Chinese herbal formulas

An interaction check asks whether these two react with each other — it does not ask whether Cnidium is a good idea for someone in your situation. Here is what our Cnidium record says about it on its own.

Cnidium: dosing

There is no well-established, standardized dose for Cnidium. Traditional formulas and modern products vary widely in strength and form.If you choose to use a Cnidium product, follow the directions on the label and do not exceed the recommended amount.

From our Cnidium monograph — the full record covers uses, side effects and every documented interaction.

Read the full Cnidium monograph & all interactions
Medication

About Tolcapone

What Is Tolcapone Used For?

Brand name: Tasmar

Tolcapone tablets are used as an add-on treatment to levodopa and carbidopa for idiopathic Parkinson's disease (Parkinson's disease with no known cause). Both Tasmar and tolcapone tablets (generic) carry this indication.

Because of a serious risk of liver failure, tolcapone is ordinarily reserved for patients who are experiencing symptom fluctuations — such as "wearing-off" episodes between doses — and who are not responding satisfactorily to, or are not appropriate candidates for, other add-on therapies.

Most-Reported Side Effects for Tolcapone

From FAERS, the FDA’s public side-effect reporting system (349 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Fall 30 reports
Hallucination 27 reports
Dyskinesia 26 reports
Pneumonia 20 reports
General physical health deterioration 19 reports
See full Tolcapone drug information
Keep checking

Other Drugs & Cnidium

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

0Major
351Moderate
0Minor
2,478No known interaction
Moderate

351 interactions

Showing 60 of 351 moderate interactions — see all 351 on the Cnidium page.

No interaction 2,478 drugs checked — show the list
Evidence & sources

Cnidium References

The 1 references that drive our Cnidium monograph and interaction data, from the evidence-graded Natural Medicines (TRC Healthcare) database. Citations with a link open the study on PubMed or the publisher’s site.

  1. Sun Y, Yang AWH, Lenon GB. Phytochemistry, ethnopharmacology, pharmacokinetics and toxicology of Cnidium monnieri (L.) Cusson. Int J Mol Sci. 2020;21(3):1006. PubMed

Medication overviews come from MedlinePlus (NIH); supplement label data from the NIH Dietary Supplement Label Database. Content is written and reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.

Pharmacist Counseling Corner

Taking Cnidium and Tolcapone Together: Common Questions

Is it safe to take Cnidium with Tolcapone?
We do not list a known interaction between Cnidium and Tolcapone. That does not guarantee the combination is risk-free, so confirm with your pharmacist or doctor — especially if you take other medications or have a health condition.
How was the Cnidium and Tolcapone combination checked?
Interactions in our licensed database are recorded against drug classes. Tolcapone is filed under 3 classifications, and Cnidium has documented interactions with 2 drug classes — none of Tolcapone's classifications are among them. A medication can belong to classes beyond those recorded in our dataset, so this describes how the check was run rather than guaranteeing safety.
Does Cnidium interact with any other medications?
Yes. Cnidium has 351 documented drug interactions in our database — Tolcapone is simply not one of them. If you take anything else, it is worth checking each one; they are all listed on this page.
Does Tolcapone interact with any supplements?
Yes. Tolcapone has documented interactions with 58 supplements in our database — Cnidium is not one of them. The Tolcapone interaction page linked on this page lists every one, ranked by severity.

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

Still Have a Question About Tolcapone and Cnidium?

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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.