Drug & supplement interaction

Eleuthero + Dextromethorphan

Dextromethorphan brand names: Hold, Benylin Adult, Benylin Pediatric, Theraflu Thin Strips Long Acting Cough, Neo Citran Thin Strips Cough.

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

Dextromethorphan falls into 2 drug categories that Eleuthero can interact with; the most serious is rated minor. Theoretically, eleuthero might increase levels of drugs metabolized by CYP2D6.

Read the full interaction report
SeverityMinor
LikelihoodUnlikely
Interactions2
EvidenceB
What do Severity, Likelihood & Evidence mean?
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Interaction report

Eleuthero and Dextromethorphan

These two interact in 2 distinct ways. Each one is explained separately below.

Why Are There 2 Interactions?

Eleuthero interacts with whole categories of medication. Dextromethorphan falls into 2 of those categories, so it can interact with Eleuthero in 2 different ways. We’ve listed each one below — your overall risk is driven by the most serious of them (Minor).

Minor

CYTOCHROME P450 2D6 (CYP2D6) SUBSTRATES

1 of 2

Why this applies to Dextromethorphan

Dextromethorphan falls under CYTOCHROME P450 2D6 (CYP2D6) SUBSTRATES — the group Eleuthero interacts with.

Theoretically, eleuthero might increase levels of drugs metabolized by CYP2D6.
In vitro and animal research suggest that standardized extracts of eleuthero might inhibit CYP2D6. However, research in healthy human volunteers has found that taking eleuthero 485 mg twice daily for 14 days does not inhibit CYP2D6 drug metabolism.
Severity Minor Likelihood Unlikely Evidence B

Interaction has been demonstrated in animal or in lab research but has been shown not to occur in humans..

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

Your body relies on an enzyme called CYP2D6 to break down dextromethorphan, the cough suppressant in products like Benylin and Theraflu. The thinking here is that eleuthero might slow that enzyme down a bit. If it did, dextromethorphan could build up and lead to stronger effects like drowsiness, dizziness, or feeling a little foggy.

Here's the reassuring part: this concern comes mostly from lab and animal studies. When researchers actually gave healthy people eleuthero (485 mg twice a day for two weeks), it did not meaningfully change CYP2D6 activity. So a real-world problem is unlikely. Still, if you take both and feel unusually sleepy or off, check in with your pharmacist or doctor.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Harkey MR, Henderson GL, Zhou L, et al. Effects of Siberian ginseng (Eleutherococcus senticosus) on c-DNA-expressed P450 drug metabolizing enzymes. Alt Ther 2001;7:S14.
  2. Donovan JL, DeVane CL, Chavin KD, et al. Siberian Ginseng (Eleutheroccus senticosus) Effects on CYP2D6 and CYP3A4 Activity in Normal Volunteers. Drug Metab Dispos 2003;31:519-22.. PubMed
Minor

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES

2 of 2

Dextromethorphan also falls under CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES.

Theoretically, eleuthero might increase levels of drugs metabolized by CYP3A4.
In vitro and animal research suggest that standardized extracts of eleuthero might inhibit CYP3A4. However, research in healthy human volunteers has found that taking eleuthero 485 mg twice daily for 14 days does not inhibit CYP3A4 drug metabolism.
Severity Minor Likelihood Unlikely Evidence B

Interaction has been demonstrated in animal or in lab research but has been shown not to occur in humans..

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

Here's the short version: in a test tube and in animals, eleuthero looked like it might slow down CYP3A4, one of the liver enzymes that helps clear dextromethorphan. If that happened in real life, your cough syrup could hang around a bit longer and you might feel more of its usual effects, like drowsiness, dizziness, or feeling a little foggy.

But here's the reassuring part. When researchers actually gave healthy people eleuthero (485 mg twice a day for two weeks), it did not meaningfully change how this enzyme works. So this concern stays mostly theoretical, and the real-world risk looks low. Dextromethorphan isn't a prodrug, so it doesn't get stronger from being activated. If you take both regularly, just mention it to your pharmacist to be safe.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Harkey MR, Henderson GL, Zhou L, et al. Effects of Siberian ginseng (Eleutherococcus senticosus) on c-DNA-expressed P450 drug metabolizing enzymes. Alt Ther 2001;7:S14.
  2. Donovan JL, DeVane CL, Chavin KD, et al. Siberian Ginseng (Eleutheroccus senticosus) Effects on CYP2D6 and CYP3A4 Activity in Normal Volunteers. Drug Metab Dispos 2003;31:519-22.. 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

Eleuthero Also Interacts With Other Medications

Eleuthero has 679 moderate, 460 minor known drug interactions in our database — the Dextromethorphan one above is among them. If you take anything else, check it against the full list below.

Moderate 679 Minor 460 No known interaction 1,691 (incl. Dextromethorphan)
Taking anything else?

Check Another of Your Medications Against Eleuthero

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

From our Q&A

Questions About Eleuthero or Dextromethorphan

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

This page covers Eleuthero only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Dextromethorphan page lists 171 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Grapefruit (major), Lithium (major), St. John's Wort (major) and 1,3-dmaa (moderate).

By severity: 4 major · 125 moderate · 42 minor.

From our pharmacist’s overview on the Dextromethorphan page

“A glass of grapefruit juice can push dextromethorphan (Benylin, Hold, and other cough medicines) to higher levels than intended, one of four major-rated entries among the 171 supplements and herbs on file, and the list as a whole warrants real care. Most interactions trace back to the liver enzymes (CYP3A4 and CYP2D6) that clear dextro…”

Reviewed by 2 · Jul 18, 2026

Open the Dextromethorphan interaction page

One more smart check

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

We hold 3,795 real supplement products containing Eleuthero, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Eleuthero. Your product may carry other ingredients that interact with Dextromethorphan too, on top of Eleuthero — 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 Eleuthero and Dextromethorphan 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 Eleuthero
Top 5%

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

29 days ago today
Medication Dextromethorphan
Top 5%

#80 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 Eleuthero

What is Eleuthero?

Eleuthero
  • Fatigue and low energy
  • Physical and athletic performance
  • Stress resistance (adaptogen)
  • Immune support
  • Mental focus and alertness

Eleuthero is an herb traditionally used as an 'adaptogen' to fight fatigue, boost energy, and help the body handle stress. The scientific evidence behind these uses is limited and mixed, so it should not replace proven treatments. It is generally well tolerated short-term, but pregnant and breastfeeding people and those with certain conditions should avoid it or check with a healthcare provider first.

Read the full Eleuthero monograph & all interactions
Medication

About Dextromethorphan

What Is Dextromethorphan Used For?

Brand names: Hold, Benylin Adult, Benylin Pediatric, Theraflu Thin Strips Long Acting Cough, Neo Citran Thin Strips Cough

Dextromethorphan temporarily relieves cough due to minor throat and bronchial irritation, such as the kind that comes with the common cold or breathing in irritants. It also helps reduce the urge to cough so you — or your child — can get to sleep.

Some products, including CVS Long Acting Cough and Premier Value Tussin Cough oral liquids, are also indicated to help loosen phlegm (mucus) and thin bronchial secretions to help drain the airways.

See full Dextromethorphan drug information
Keep checking

Other Drugs & Eleuthero

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

0Major
679Moderate
460Minor
1,690No known interaction
679 Moderate 460 Minor 1,690 No interaction
Moderate

679 interactions

Showing 60 of 679 moderate interactions — see all 679 on the Eleuthero page.

Minor

460 interactions

Showing 60 of 460 minor interactions — see all 460 on the Eleuthero page.

No interaction 1,690 drugs checked — show the list

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

Showing the 60 most looked-up of 1,690 medications checked with no known interaction — see the full Eleuthero list.

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

Can you take Eleuthero with Dextromethorphan?
There is only a minor interaction, which is usually not serious. Read the full details on this page and confirm with your pharmacist before combining them.
Why are there 2 interactions listed for Eleuthero and Dextromethorphan?
Dextromethorphan belongs to more than one drug category, and Eleuthero 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 Eleuthero and Dextromethorphan interaction?
We rate it Minor. This interaction is generally not clinically significant, but it remains worth noting and discussing with your pharmacist.

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

Still Have a Question About Dextromethorphan and Eleuthero?

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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.