Drug & supplement interaction

Thyme + Trihexyphenidyl

Trihexyphenidyl brand names: Artane, Trihex, Artane Sequels.

Moderate Interaction
The bottom line Moderate

Thyme has a moderate interaction with Trihexyphenidyl. Theoretically, concurrent use of anticholinergic drugs and thyme essential oil might reduce the effects of anticholinergic drugs.

Read the full interaction report
SeverityModerate
LikelihoodPossible
EvidenceD
What do Severity, Likelihood & Evidence mean?
Know someone taking this? Share
Interaction report

Thyme and Trihexyphenidyl

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

Moderate

ANTICHOLINERGIC DRUGS

Why this applies to Trihexyphenidyl

Trihexyphenidyl falls under ANTICHOLINERGIC DRUGS — the group Thyme interacts with.

Theoretically, concurrent use of anticholinergic drugs and thyme essential oil might reduce the effects of anticholinergic drugs.
In vitro evidence suggests that thyme essential oil and specific essential oil constituents like thymohydroquinone and carvacrol can inhibit acetylcholinesterase (AChE). However, this effect has not been observed 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 idea behind this one. Trihexyphenidyl works by blocking acetylcholine, a nerve-signaling chemical, which helps ease tremor and stiffness in Parkinson's. Lab studies hint that compounds in thyme essential oil (like thymol and carvacrol) might raise acetylcholine levels by slowing the enzyme that breaks it down. If that happened in your body, it could work against trihexyphenidyl and make it a little less effective, meaning more tremor or muscle symptoms could sneak back.

But here's the reassuring part: this was only seen in test-tube studies, never in actual people, and the everyday thyme you cook with is very unlikely to matter. Concentrated thyme essential oil is a different story, and it should never be swallowed anyway. If you're thinking about thyme supplements, just run it by your pharmacist or doctor first.

References
  1. Jukic, M., Politeo, O., Maksimovic, M., Milos, M., and Milos, M. In vitro acetylcholinesterase inhibitory properties of thymol, carvacrol and their derivatives thymoquinone and thymohydroquinone. Phytother.Res 2007;21(3):259-261.

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

Thyme Also Interacts With Other Medications

Thyme has 378 moderate known drug interactions in our database — the Trihexyphenidyl one above is one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Thyme

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

Everything else you take

See Every Supplement That Interacts With Trihexyphenidyl

This page covers Thyme only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Trihexyphenidyl page lists 46 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Henbane (major), Scopolia (major), Angel's Trumpet (moderate) and Bacopa (moderate).

By severity: 3 major · 32 moderate · 11 minor.

From our pharmacist’s overview on the Trihexyphenidyl page

“Trihexyphenidyl (Artane) calms the tremor of Parkinson's disease and the muscle stiffness some antipsychotic drugs cause, and this is a list worth reading closely, since three of its 46 flagged ingredients carry a major rating. Two of those are herbs with the same atropine-like chemistry as the drug itself, piling on dry mouth, blurred…”

Reviewed by 2 · Jul 18, 2026

Open the Trihexyphenidyl interaction page

One more smart check

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

We hold 708 real supplement products containing Thyme, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Thyme. Your product may carry other ingredients that interact with Trihexyphenidyl too, on top of Thyme — 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 Thyme and Trihexyphenidyl 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 Thyme
Top 25%

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

29 days ago today
Medication Trihexyphenidyl
Steady interest

#1,814 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 Thyme

What is Thyme?

Thyme
  • Cough and respiratory congestion
  • Sore throat
  • Digestive upset
  • Antimicrobial and antiseptic uses
  • Flavoring in cooking

Thyme is a common kitchen herb that has long been used for coughs, sore throats, and digestive complaints. It is generally safe in the amounts found in food, and some cough products that combine thyme with other herbs have modest supporting evidence, but high-quality research on thyme alone is limited. The concentrated essential oil should never be swallowed undiluted.

Read the full Thyme monograph & all interactions
Medication

About Trihexyphenidyl

What Is Trihexyphenidyl Used For?

Brand names: Artane, Trihex, Artane Sequels

Trihexyphenidyl is used as part of treatment for all forms of parkinsonism — including idiopathic (the most common type), postencephalitic (following a brain infection), and arteriosclerotic parkinsonism. It is often added alongside levodopa when levodopa alone isn't fully controlling symptoms.

It is also used to control extrapyramidal reactions (involuntary movement problems) that can be caused by certain psychiatric drugs, including phenothiazines, thioxanthenes, butyrophenones, and dibenzoxazepines.

See full Trihexyphenidyl drug information
Keep checking

Other Drugs & Thyme

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

0Major
378Moderate
0Minor
2,451No known interaction
Moderate

378 interactions

Showing 60 of 378 moderate interactions — see all 378 on the Thyme page.

No interaction 2,451 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

Keep exploring
Pharmacist Counseling Corner

Taking Thyme and Trihexyphenidyl Together: Common Questions

Can you take Thyme with Trihexyphenidyl?
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 Thyme and Trihexyphenidyl 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 Trihexyphenidyl and Thyme?

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.