Drug & supplement interaction

Evodia + Isoniazid, Rifampin

Isoniazid, Rifampin brand name: Rifamate.

Moderate Interaction
The bottom line Moderate

Isoniazid, Rifampin falls into 3 drug categories that Evodia can interact with; the most serious is rated moderate. Theoretically, CYP3A4 inhibitors might increase the levels and clinical effects of evodia.

Read the full interaction report
SeverityModerate
LikelihoodPossible
Interactions3
EvidenceD
What do Severity, Likelihood & Evidence mean?
Know someone taking this? Share
Interaction report

Evodia and Isoniazid, Rifampin

These two interact in 3 distinct ways. Each one is explained separately below.

Why Are There 3 Interactions?

Evodia interacts with whole categories of medication. Isoniazid, Rifampin falls into 3 of those categories, so it can interact with Evodia in 3 different ways. We’ve listed each one below — your overall risk is driven by the most serious of them (Moderate).

Moderate

CYTOCHROME P450 3A4 (CYP3A4) INHIBITORS

1 of 3

Why this applies to Isoniazid, Rifampin

Isoniazid, Rifampin falls under CYTOCHROME P450 3A4 (CYP3A4) INHIBITORS — the group Evodia interacts with.

Theoretically, CYP3A4 inhibitors might increase the levels and clinical effects of evodia.
Animal research shows that concomitant administration of ketoconazole, a known CYP3A4 inhibitor, with the alkaloid constituents of evodia significantly increases the area under the curve (AUC), maximum concentration (Cmax), and half-life of these constituents.
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 to know about this pairing: the interaction runs in an unexpected direction. The medication in Rifamate combines isoniazid and rifampin, and the isoniazid piece can block a liver enzyme called CYP3A4. Evodia happens to be cleared by that same enzyme. So if you slow that enzyme down, evodia can hang around longer in your body and build up to higher levels than usual.

In plain terms, it's the evodia that may become stronger, not your TB medicine. That could mean more of evodia's own effects or side effects, though honestly this is based only on lab and animal studies, so we don't really know how much it matters in people. I'd just run it past your pharmacist or doctor before combining them, especially since these TB drugs are important to keep working right.

References
  1. Zhang W, Guo J, Wang D, et al. Effect of CYP3A inducer/inhibitor on pharmacokinetics of five alkaloids in Evodiae Fructus. Chem Biol Interact 2020;327:109146. PubMed
Moderate

CYTOCHROME P450 1A2 (CYP1A2) INHIBITORS

2 of 3

Isoniazid, Rifampin also falls under CYTOCHROME P450 1A2 (CYP1A2) INHIBITORS.

Theoretically, drugs that inhibit CYP1A2 might increase the levels and clinical effects of evodia.
The evodia constituent rutaecarpine is metabolized by CYP1A2.
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 to keep in mind with this combo: the concern runs toward the Evodia, not toward your Rifamate (isoniazid plus rifampin). Isoniazid can act like a brake on a liver enzyme called CYP1A2, which is the same enzyme that helps clear one of Evodia's active compounds (rutaecarpine). If that brake slows things down, the Evodia compound could build up and its effects, whatever they may be, might feel stronger than expected.

I'll be honest with you, this is purely a theoretical, test-tube and animal idea, not something proven in people, so I wouldn't lose sleep over it. Still, since Evodia isn't well studied and your TB medicines are important, I'd run it past your pharmacist or doctor before combining them.

References
  1. Lee SK, Kim NH, Lee J, et al. Induction of cytochrome P450s by rutaecarpine and metabolism of rutaecarpine by cytochrome P450s. Planta Med 2004;70:753-7. PubMed
Moderate

CYTOCHROME P450 3A4 (CYP3A4) INDUCERS

3 of 3

Isoniazid, Rifampin also falls under CYTOCHROME P450 3A4 (CYP3A4) INDUCERS.

Theoretically, taking CYP3A4 inducers might decrease the levels and clinical effects of evodia.
Animal research shows that concomitant administration of dexamethasone, a known CYP3A4 inducer, with the alkaloid constituents of evodia significantly reduces the area under the curve (AUC), maximum concentration (Cmax), and half-life of these constituents.
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 if you take Rifamate (which combines isoniazid and rifampin) and are curious about evodia. Rifampin is one of the strongest natural "speed-up" signals for a liver enzyme called CYP3A4. Evodia's active compounds (like evodiamine) appear to be broken down by that same enzyme. So the concern isn't that evodia changes your TB medicine. It's the reverse: rifampin may rev up your liver and clear evodia out faster, leaving you with lower, possibly less effective levels of the supplement.

I want to be honest that this is theoretical, based on animal and lab work, not human studies. There's no good evidence it's dangerous. Still, since these antibiotics are important, please run any supplement by your pharmacist or doctor before adding it.

References
  1. Zhang W, Guo J, Wang D, et al. Effect of CYP3A inducer/inhibitor on pharmacokinetics of five alkaloids in Evodiae Fructus. Chem Biol Interact 2020;327:109146. 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 Isoniazid, Rifampin one above is among them. If you take anything else, check it against the full list below.

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.

Everything else you take

See Every Supplement That Interacts With Isoniazid, Rifampin

This page covers Evodia only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Isoniazid, Rifampin page lists 145 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Apple (major), Asarabacca (major), Beer (major) and Grapefruit (major).

By severity: 8 major · 117 moderate · 20 minor.

From our pharmacist’s overview on the Isoniazid, Rifampin page

“Rifamate combines isoniazid and rifampin, the backbone of tuberculosis treatment, and both drugs are hard on the liver, which is why this list of 145 supplement and herbal interactions deserves genuine respect. Eight entries rate major, and the largest cluster, 38 ingredients, adds to that same liver strain, with alcohol in beer or win…”

Reviewed by 2 · Jul 18, 2026

Open the Isoniazid, Rifampin 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 Isoniazid, Rifampin 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 Isoniazid, Rifampin 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

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

29 days ago today
Medication Isoniazid, Rifampin
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
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
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
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 Evodia and Isoniazid, Rifampin Together: Common Questions

Can you take Evodia with Isoniazid, Rifampin?
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.
Why are there 3 interactions listed for Evodia and Isoniazid, Rifampin?
Isoniazid, Rifampin belongs to more than one drug category, and Evodia 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 Evodia and Isoniazid, Rifampin 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 Isoniazid, Rifampin and Evodia?

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.