Drug & supplement interaction

Dandelion + Acetaminophen, Codeine, Doxylamine

Acetaminophen, Codeine, Doxylamine brand name: Mersyndol.

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

Acetaminophen, Codeine, Doxylamine falls into 2 drug categories that Dandelion can interact with; the most serious is rated moderate. Theoretically, dandelion might increase levels of drugs metabolized by CYP1A2.

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

Dandelion and Acetaminophen, Codeine, Doxylamine

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

Why Are There 2 Interactions?

Dandelion interacts with whole categories of medication. Acetaminophen, Codeine, Doxylamine falls into 2 of those categories, so it can interact with Dandelion 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 1A2 (CYP1A2) SUBSTRATES

1 of 2

Why this applies to Acetaminophen, Codeine, Doxylamine

Acetaminophen, Codeine, Doxylamine falls under CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES — the group Dandelion interacts with.

Theoretically, dandelion might increase levels of drugs metabolized by CYP1A2.
Laboratory research suggests that dandelion might inhibit CYP1A2. So far, this interaction has not been reported in humans. However, until more is known, watch for an increase in the levels of drugs metabolized by CYP1A2 in patients taking dandelion.
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 honest picture with Mersyndol (acetaminophen, codeine, and doxylamine) and dandelion. The concern is based only on lab studies suggesting dandelion might slow down a liver enzyme called CYP1A2. This has never actually been reported in real people, so think of it as a theoretical caution, not a proven problem.

If dandelion did slow that enzyme even a little, levels of these medicines could creep up, which might mean more drowsiness, dizziness, constipation, or feeling foggy, since both codeine and doxylamine already cause sedation. Eating dandelion in food almost certainly won't matter. With concentrated supplements, just give your pharmacist or doctor a quick heads-up before combining them.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Maliakal PP, Wanwimolruk S. Effect of herbal teas on hepatic drug metabolizing enzymes in rats. J Pharm Pharmacol 2001;53:1323-9. PubMed
Moderate

GLUCURONIDATED DRUGS

2 of 2

Acetaminophen, Codeine, Doxylamine also falls under GLUCURONIDATED DRUGS.

Theoretically, dandelion might increase the clearance of drugs that are UDP-glucuronosyltransferase substrates.
There is some preliminary evidence that dandelion might induce UDP-glucuronosyltransferase, a phase II enzyme.
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 with Mersyndol (which combines acetaminophen, codeine, and doxylamine) and dandelion. Your body clears acetaminophen partly through a process called glucuronidation. Lab and animal studies hint that dandelion might speed up that enzyme, which in theory could clear the acetaminophen a little faster and make it slightly less effective for pain or fever. Importantly, this is very weak, test-tube level evidence, so I wouldn't lose sleep over it.

One thing worth a mention: codeine is a sedating opioid and doxylamine is a drowsy antihistamine, so this product already packs a sleepy punch. Eating dandelion in foods is unlikely to matter, but before using concentrated dandelion supplements alongside Mersyndol, just run it by your pharmacist or doctor.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Maliakal PP, Wanwimolruk S. Effect of herbal teas on hepatic drug metabolizing enzymes in rats. J Pharm Pharmacol 2001;53:1323-9. 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

Dandelion Also Interacts With Other Medications

Dandelion has 456 moderate known drug interactions in our database — the Acetaminophen, Codeine, Doxylamine one above is among them. If you take anything else, check it against the full list below.

Moderate 456 No known interaction 2,374 (incl. Acetaminophen, Codeine, Doxylamine)
Taking anything else?

Check Another of Your Medications Against Dandelion

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

From our Q&A

Questions About Dandelion or Acetaminophen, Codeine, Doxylamine

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

This page covers Dandelion only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Acetaminophen, Codeine, Doxylamine page lists 261 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: 1,4-butanediol (major), Activated Charcoal (major), Asarabacca (major), Beer (major) and Gamma-hydroxybutyrate (ghb) (major).

By severity: 11 major · 208 moderate · 42 minor.

From our pharmacist’s overview on the Acetaminophen, Codeine, Doxylamine page

“Mersyndol pairs acetaminophen with codeine and doxylamine, two sedating drugs in one tablet, so I read its interaction list with genuine vigilance. Of the 261 supplements and herbs on file, the biggest hazard is anything else that slows the brain: 78 ingredients add sedation, and that group holds several of the 11 major-rated entries,…”

Reviewed by 2 · Jul 18, 2026

Open the Acetaminophen, Codeine, Doxylamine interaction page

One more smart check

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

We hold 4,328 real supplement products containing Dandelion, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Dandelion. Your product may carry other ingredients that interact with Acetaminophen, Codeine, Doxylamine too, on top of Dandelion — 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 Dandelion and Acetaminophen, Codeine, Doxylamine 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 Dandelion
Top 5%

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

29 days ago today
Medication Acetaminophen, Codeine, Doxylamine
Steady interest

#1,531 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 Dandelion

What is Dandelion?

Dandelion
  • Water retention (diuretic)
  • Digestive upset
  • Liver and gallbladder support
  • Mild appetite stimulant
  • Skin conditions

Dandelion is a common plant used in food and traditional medicine, often promoted as a natural 'water pill' and digestive aid. Human evidence for these uses is very limited, so its benefits are not well proven. It is generally considered safe as a food, but talk to your pharmacist or doctor before using concentrated supplements, especially if you have allergies or take other medicines.

Read the full Dandelion monograph & all interactions
Keep checking

Other Drugs & Dandelion

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

0Major
456Moderate
0Minor
2,373No known interaction
456 Moderate 2,373 No interaction
Moderate

456 interactions

Showing 60 of 456 moderate interactions — see all 456 on the Dandelion page.

No interaction 2,373 drugs checked — show the list

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

Showing the 60 most looked-up of 2,373 medications checked with no known interaction — see the full Dandelion list.

See the full Dandelion interactions page
See every supplement checked against Acetaminophen, Codeine, Doxylamine, 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
Dandelion monograph › Uses, safety, and every drug interaction in one place Acetaminophen, Codeine, Doxylamine supplement interactions › Every supplement checked against Acetaminophen, Codeine, Doxylamine, 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 Dandelion and Acetaminophen, Codeine, Doxylamine Together: Common Questions

Can you take Dandelion with Acetaminophen, Codeine, Doxylamine?
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 Dandelion and Acetaminophen, Codeine, Doxylamine?
Acetaminophen, Codeine, Doxylamine belongs to more than one drug category, and Dandelion 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 Dandelion and Acetaminophen, Codeine, Doxylamine 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

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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.