Drug & supplement interaction

German Chamomile + Dextromethorphan

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

Moderate Interaction
The bottom line Moderate

Dextromethorphan falls into 2 drug categories that German Chamomile can interact with; the most serious is rated moderate. Theoretically, German chamomile might inhibit CYP2D6 and increase levels of drugs metabolized by these enzymes.

Read the full interaction report
SeverityModerate
LikelihoodPossible
Interactions2
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

German Chamomile and Dextromethorphan

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

Why Are There 2 Interactions?

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

Moderate

CYTOCHROME P450 2D6 (CYP2D6) SUBSTRATES

1 of 2

Why this applies to Dextromethorphan

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

Theoretically, German chamomile might inhibit CYP2D6 and increase levels of drugs metabolized by these enzymes.
In vitro evidence shows that German chamomile might inhibit CYP2D6. So far, this interaction has not been reported in humans. However, there might be an increase in the levels of drugs metabolized by CYP2D6 in patients taking German chamomile.
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 simple version: your body relies on a liver enzyme called CYP2D6 to clear dextromethorphan out of your system. German chamomile may slow that enzyme down a bit, at least in lab dish studies. If it does, dextromethorphan could hang around longer and build up, which might mean more of its typical effects, things like drowsiness, dizziness, or feeling lightheaded or foggy.

The good news is that this is mostly a theory right now. It comes from test-tube research, and it hasn't actually been reported in real people sipping chamomile tea. A cup of tea is unlikely to cause trouble, but concentrated chamomile supplements are less predictable. If you notice extra grogginess, just check in with your pharmacist or doctor.

References
  1. Ganzera M, Schneider P, Stuppner H. Inhibitory effects of the essential oil of chamomile (Matricaria recutita L.) and its major constituents on human cytochrome P450 enzymes. Life Sci 2006;78(8):856-861. PubMed
Moderate

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES

2 of 2

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

Theoretically, German chamomile might inhibit CYP3A4 and increase levels of drugs metabolized by these enzymes.
In vitro evidence shows that German chamomile might inhibit CYP3A4. So far, this interaction has not been reported in humans. However, there might be an increase in the levels of drugs metabolized by CYP3A4 in patients taking German chamomile.
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 like a cup of chamomile tea while fighting off a cough. Your body uses liver enzymes, including one called CYP3A4, to help break down and clear dextromethorphan. In a test-tube setting, chamomile appeared to slow that enzyme down a bit. In theory, that could let a little more dextromethorphan hang around, which might bump up its usual effects like drowsiness, dizziness, or feeling foggy.

I want to be straight with you though: this is only lab data and has not been seen in real people. A normal mug of chamomile tea is very unlikely to cause trouble. If you're using concentrated chamomile supplements or just feel unusually groggy, check in with your pharmacist or doctor.

References
  1. Budzinski JW, Foster BC, Vandenhoek S, Arnason JT. An in vitro evaluation of human cytochrome P450 3A4 inhibition by selected commercial herbal extracts and tinctures. Phytomedicine 2000;7:273-82. PubMed
  2. Ganzera M, Schneider P, Stuppner H. Inhibitory effects of the essential oil of chamomile (Matricaria recutita L.) and its major constituents on human cytochrome P450 enzymes. Life Sci 2006;78(8):856-861. 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

German Chamomile Also Interacts With Other Medications

German Chamomile has 924 moderate, 35 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.

Taking anything else?

Check Another of Your Medications Against German Chamomile

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

From our Q&A

Questions About German Chamomile 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 German Chamomile 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 German Chamomile 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 German Chamomile as Part of a Dietary Supplement Product? Check It for Interactions

We hold 782 real supplement products containing German Chamomile, each one broken down to its full ingredient list — and combination products often carry several ingredients besides German Chamomile. Your product may carry other ingredients that interact with Dextromethorphan too, on top of German Chamomile — 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 German Chamomile 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 German Chamomile
Top 25%

#250 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 German Chamomile

What is German Chamomile?

German Chamomile
  • Anxiety and stress
  • Sleep and relaxation
  • Digestive upset
  • Skin irritation and inflammation
  • Mouth sores and gum irritation

German chamomile is a widely used herbal remedy taken mainly as a tea for calming, sleep, and digestive complaints. Early research suggests possible benefits for mild anxiety and some skin or digestive issues, but the evidence is limited and most uses are based on tradition rather than strong proof. It is generally well tolerated, but people allergic to ragweed or related plants and those who are pregnant should be cautious.

Read the full German Chamomile 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 & German Chamomile

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

0Major
924Moderate
35Minor
1,870No known interaction
Moderate

924 interactions

Showing 60 of 924 moderate interactions — see all 924 on the German Chamomile page.

Minor

35 interactions

No interaction 1,870 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

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Pharmacist Counseling Corner

Taking German Chamomile and Dextromethorphan Together: Common Questions

Can you take German Chamomile with Dextromethorphan?
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 2 interactions listed for German Chamomile and Dextromethorphan?
Dextromethorphan belongs to more than one drug category, and German Chamomile 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 German Chamomile and Dextromethorphan 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 Dextromethorphan and German Chamomile?

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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.