Drug & supplement interaction

Evodia + Chlorzoxazone

Chlorzoxazone brand names: Parafon Forte DSC, Paraflex.

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

Evodia has a moderate interaction with Chlorzoxazone. Theoretically, evodia might decrease the levels and clinical effects of chlorzoxazone.

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

Evodia and Chlorzoxazone

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

Moderate

CHLORZOXAZONE (Parafon Forte, Paraflex)

Theoretically, evodia might decrease the levels and clinical effects of chlorzoxazone.
Animal research shows that administration of rutaecarpine, a constituent of evodia, with chlorzoxazone reduces the area under the curve (AUC) of chlorzoxazone by 84% and increases its clearance by 646%. This interaction is likely due to induction of cytochrome P450 2E1 (CYP2E1) by rutaecarpine .
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 these two together. Chlorzoxazone is a muscle relaxer that your liver clears using an enzyme called CYP2E1. Evodia contains a compound (rutaecarpine) that appears to speed up that enzyme. If the enzyme works faster, your body removes chlorzoxazone more quickly, so there's less of it around to do its job. In plain terms, your muscle pain and stiffness might not get the relief you were hoping for.

One important thing: this is based on animal and lab research only, not studies in people, so we can't say for sure how much it matters in real life. Before pairing Evodia with chlorzoxazone, it's worth a quick chat with your pharmacist or doctor so they can keep an eye on how well your muscle relief is holding up.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Bista SR, Lee SK, Thapa D, et al. Effects of oral rutaecarpine on the pharmacokinetics of intravenous chlorzoxazone in rats. Toxicol Res 2008;24(3):195-9. 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

Evodia Also Interacts With Other Medications

Evodia has 949 moderate known drug interactions in our database — the Chlorzoxazone one above is one of them. If you take anything else, check it against the full list below.

Moderate 949 No known interaction 1,881 (incl. Chlorzoxazone)
Taking anything else?

Check Another of Your Medications Against Evodia

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

From our Q&A

Questions About Evodia or Chlorzoxazone

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

This page covers Evodia only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Chlorzoxazone page lists 26 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Procaine (major), Coffee Charcoal (moderate), Diosmin (moderate) and European Mandrake (moderate).

By severity: 2 major · 15 moderate · 9 minor.

From our pharmacist’s overview on the Chlorzoxazone page

“Chlorzoxazone (Parafon Forte DSC, Paraflex) is a muscle relaxant for painful spasms, and its supplement list is one I want readers genuinely careful with. Twenty-six ingredients are on file, two rated major, led by activated charcoal, which can soak up the drug in the gut and cut what your body actually receives.”

Reviewed by 2 · Jul 18, 2026

Open the Chlorzoxazone interaction page

One more smart check

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

We hold 182 real supplement products containing Evodia, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Evodia. Your product may carry other ingredients that interact with Chlorzoxazone too, on top of Evodia — 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 Evodia and Chlorzoxazone 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 Evodia
Top half

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

29 days ago today
Medication Chlorzoxazone
Top half

#979 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 Evodia

What is Evodia?

  • Digestive upset and nausea
  • Headaches
  • Menstrual cramps
  • Abdominal pain
  • Diarrhea

Evodia is a fruit used in traditional Chinese medicine, most often for digestive complaints, headaches, and menstrual pain. Human evidence for these uses is very limited, and it is mostly studied in laboratory and animal research. Talk with a pharmacist or doctor before using it, and avoid it during pregnancy and breastfeeding.

Read the full Evodia monograph & all interactions
Medication

About Chlorzoxazone

What Is Chlorzoxazone Used For?

Brand names: Parafon Forte DSC, Paraflex

Chlorzoxazone tablets are used to relieve discomfort caused by acute, painful musculoskeletal conditions — things like muscle spasms and the pain that comes with them. It is meant to be used alongside rest, physical therapy, and other treatments, not as a stand-alone cure.

It is not intended for long-term muscle problems; it's most useful during a short-term flare of muscle pain and stiffness.

See full Chlorzoxazone drug information
Keep checking

Other Drugs & Evodia

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

0Major
949Moderate
0Minor
1,880No known interaction
949 Moderate 1,880 No interaction
Moderate

949 interactions

Showing 60 of 949 moderate interactions — see all 949 on the Evodia page.

No interaction 1,880 drugs checked — show the list

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

Showing the 60 most looked-up of 1,880 medications checked with no known interaction — see the full Evodia list.

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

Can you take Evodia with Chlorzoxazone?
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 Evodia and Chlorzoxazone 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 Chlorzoxazone and Evodia?

Our pharmacists answer your medication & supplement questions — free.

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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.