Drug & supplement interaction

Echinacea + acetaminophen, dextromethorphan, phenylephrine, guaifenesin

acetaminophen, dextromethorphan, phenylephrine, guaifenesin brand name: DayQuil Severe.

Minor Interaction
Medically reviewed by · Updated March 2023
The bottom line Minor

Echinacea has a minor interaction with acetaminophen, dextromethorphan, phenylephrine, guaifenesin. Echinacea is reported to have varying effects on a number of Cytochrome P450 metabolizing enzymes in the liver, including CYP1A2 and CYP3A4, which play a role in acetaminophen and dextromethorphan metabolism (both contained in DayQuil Severe), respectively.

Read the full interaction report
SeverityMinor
LikelihoodUnlikely
EvidenceA
What do Severity, Likelihood & Evidence mean?
Know someone taking this? Share
Facebook Post Reddit Email
On this page
Interaction report

Echinacea and acetaminophen, dextromethorphan, phenylephrine, guaifenesin

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

Minor

DayQuil Severe

Why this applies to acetaminophen, dextromethorphan, phenylephrine, guaifenesin

acetaminophen, dextromethorphan, phenylephrine, guaifenesin falls under DayQuil Severe — the group Echinacea interacts with.

Echinacea is reported to have varying effects on a number of Cytochrome P450 metabolizing enzymes in the liver, including CYP1A2 and CYP3A4, which play a role in acetaminophen and dextromethorphan metabolism (both contained in DayQuil Severe), respectively. Studies have reported both enzyme inhibition and induction, making it difficult to predict clinically significant drug interactions with reliability. Specific drug interaction studies reporting definitive results are rare, and potential drug interactions involving echinacea should likely be taken on a case-by-case basis. Based on what we know about how acetaminophen and dextromethorphan are metabolized, the risk of a clinically significant interaction between echinacea and DayQuil Severe is low.
Severity Minor Likelihood Unlikely Evidence A

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: if you're taking echinacea while using DayQuil Severe for a cold, you really don't have much to worry about. Echinacea has been reported to nudge certain liver enzymes (like CYP1A2 and CYP3A4) that help process the acetaminophen and dextromethorphan in this product. The catch is that studies have shown echinacea both speeding up and slowing down these enzymes, so we can't reliably predict any one effect.

In plain terms, it's very unlikely to meaningfully change how DayQuil works or to make side effects like drowsiness, dizziness, or stomach upset worse. Just keep your total acetaminophen in mind across all products so you don't go over the daily limit. If you take echinacea regularly or have liver concerns, a quick word with your pharmacist is a smart move.

Contact Dr. Brian directly if you have additional questions on this interaction

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

Echinacea Also Interacts With Other Medications

Echinacea has 815 moderate known drug interactions in our database — the acetaminophen, dextromethorphan, phenylephrine, guaifenesin one above is one of them. If you take anything else, check it against the full list below.

Moderate 815 No known interaction 2,015 (incl. acetaminophen, dextromethorphan, phenylephrine, guaifenesin)
Taking anything else?

Check Another of Your Medications Against Echinacea

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

From our Q&A

Questions About Echinacea or acetaminophen, dextromethorphan, phenylephrine, guaifenesin

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Echinacea or acetaminophen, dextromethorphan, phenylephrine, guaifenesin, 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 acetaminophen, dextromethorphan, phenylephrine, guaifenesin

This page covers Echinacea only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the acetaminophen, dextromethorphan, phenylephrine, guaifenesin page lists 1 supplement it has a documented interaction with, worst first, each one explained.

By severity: 1 minor.

From our pharmacist’s overview on the acetaminophen, dextromethorphan, phenylephrine, guaifenesin page

“People fighting off a cold with DayQuil Severe (acetaminophen, dextromethorphan, phenylephrine, guaifenesin) are often the same people dosing themselves with echinacea, and that pairing is the only supplement interaction on record here, rated minor and considered unlikely to matter. Echinacea can nudge the liver enzymes that break down…”

Reviewed by 2 · Jul 18, 2026

Open the acetaminophen, dextromethorphan, phenylephrine, guaifenesin interaction page

One more smart check

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

We hold 350 real supplement products containing Echinacea, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Echinacea. Your product may carry other ingredients that interact with acetaminophen, dextromethorphan, phenylephrine, guaifenesin too, on top of Echinacea — 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 Echinacea and acetaminophen, dextromethorphan, phenylephrine, guaifenesin 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 Echinacea
Top 5%

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

29 days ago today
Medication acetaminophen, dextromethorphan, phenylephrine, guaifenesin
Steady interest

#1,703 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 Echinacea

What is Echinacea?

Echinacea
  • Common cold
  • Flu and respiratory infections
  • Immune support
  • Sore throat
  • Wound and skin care (traditional)

Echinacea is a popular herb taken to help prevent or shorten the common cold, but study results are mixed and the overall benefit appears small at best. It is generally well tolerated for short-term use in most healthy adults, though people with allergies to daisy-family plants and those who are pregnant or breastfeeding should be cautious and talk to a pharmacist or doctor first.

Read the full Echinacea monograph & all interactions
Keep checking

Other Drugs & Echinacea

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

0Major
815Moderate
0Minor
2,014No known interaction
815 Moderate 2,014 No interaction
Moderate

815 interactions

Showing 60 of 815 moderate interactions — see all 815 on the Echinacea page.

No interaction 2,014 drugs checked — show the list

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

Showing the 60 most looked-up of 2,014 medications checked with no known interaction — see the full Echinacea list.

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

Can you take Echinacea with acetaminophen, dextromethorphan, phenylephrine, guaifenesin?
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.
How serious is the Echinacea and acetaminophen, dextromethorphan, phenylephrine, guaifenesin 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 acetaminophen, dextromethorphan, phenylephrine, guaifenesin and Echinacea?

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.