Drug & supplement interaction

Hemp + Acetaminophen, Chlorpheniramine Maleate, Dextromethorphan HBr

Acetaminophen, Chlorpheniramine Maleate, Dextromethorphan HBr brand name: Vicks Formula 44M Cough, Cold & Flu Relief.

Minor Interaction
The bottom line Minor

Acetaminophen, Chlorpheniramine Maleate, Dextromethorphan HBr falls into 2 drug categories that Hemp can interact with; the most serious is rated minor. Theoretically, hemp might decrease the levels and clinical effects of CYP1A2 substrates.

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

Hemp and Acetaminophen, Chlorpheniramine Maleate, Dextromethorphan HBr

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

Why Are There 2 Interactions?

Hemp interacts with whole categories of medication. Acetaminophen, Chlorpheniramine Maleate, Dextromethorphan HBr falls into 2 of those categories, so it can interact with Hemp 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 1A2 (CYP1A2) SUBSTRATES

1 of 2

Why this applies to Acetaminophen, Chlorpheniramine Maleate, Dextromethorphan HBr

Acetaminophen, Chlorpheniramine Maleate, Dextromethorphan HBr falls under CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES — the group Hemp interacts with.

Theoretically, hemp might decrease the levels and clinical effects of CYP1A2 substrates.
In vitro research shows that hemp induces CYP1A2 enzymes.
Severity Minor 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 this cough, cold, and flu combo (acetaminophen for pain and fever, chlorpheniramine for runny nose and sneezing, and dextromethorphan to quiet a cough). Some lab studies suggest hemp may gently speed up a liver enzyme called CYP1A2. If that happened in the body, it could clear certain medicines a little faster, which might make them work slightly less well. None of these three ingredients lean heavily on CYP1A2, so any real-world effect would likely be small.

Honestly, this is theoretical and based only on test-tube research, so I wouldn't lose sleep over it. Eating hemp seeds or hemp oil as food is very unlikely to matter. If you use concentrated hemp supplements regularly, just mention it to your pharmacist to be safe.

References
  1. Haron MH, Dale O, Martin K, et al. Evaluation of the Herb-Drug Interaction Potential of Commonly Used Botanicals on the US Market with Regard to PXR- and AhR-Mediated Influences on CYP3A4 and CYP1A2. J Diet Suppl 2022. PubMed
Minor

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES

2 of 2

Acetaminophen, Chlorpheniramine Maleate, Dextromethorphan HBr also falls under CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES.

Theoretically, hemp might decrease the levels and clinical effects of CYP3A4 substrates.
In vitro research shows that hemp induces CYP3A4 enzymes.
Severity Minor 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

This Vicks combo pulls together three ingredients: acetaminophen (the pain and fever reducer), chlorpheniramine (an antihistamine), and dextromethorphan (the cough suppressant). The idea on file is that hemp might gently speed up an enzyme in your liver called CYP3A4, which helps break down dextromethorphan. In theory, that could clear it a little faster and make it slightly less effective at quieting your cough.

Here's the honest part: this is only suggested by lab and test-tube research, not real-world patient cases, so it's rated minor. Everyday hemp seeds or hemp oil in food are very unlikely to cause any noticeable change. If you're taking concentrated hemp supplements, it's worth a quick chat with your pharmacist, but there's no reason to be alarmed.

References
  1. Haron MH, Dale O, Martin K, et al. Evaluation of the Herb-Drug Interaction Potential of Commonly Used Botanicals on the US Market with Regard to PXR- and AhR-Mediated Influences on CYP3A4 and CYP1A2. J Diet Suppl 2022. 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

Hemp Also Interacts With Other Medications

Hemp has 41 moderate, 898 minor known drug interactions in our database — the Acetaminophen, Chlorpheniramine Maleate, Dextromethorphan HBr 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 Hemp

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

Everything else you take

See Every Supplement That Interacts With Acetaminophen, Chlorpheniramine Maleate, Dextromethorphan HBr

This page covers Hemp only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Acetaminophen, Chlorpheniramine Maleate, Dextromethorphan HBr page lists 275 supplements it has a documented interaction with, worst first, each one explained.

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

By severity: 10 major · 220 moderate · 45 minor.

From our pharmacist’s overview on the Acetaminophen, Chlorpheniramine Maleate, Dextromethorphan HBr page

“A three-drug cold formula like Vicks Formula 44M (acetaminophen, chlorpheniramine, and dextromethorphan) gives supplements three separate targets, so its interaction list warrants real vigilance, starting with the ten major-rated entries. The dominant patterns track each ingredient.”

Reviewed by 2 · Jul 18, 2026

Open the Acetaminophen, Chlorpheniramine Maleate, Dextromethorphan HBr interaction page

One more smart check

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

We hold 720 real supplement products containing Hemp, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Hemp. Your product may carry other ingredients that interact with Acetaminophen, Chlorpheniramine Maleate, Dextromethorphan HBr too, on top of Hemp — 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 Hemp and Acetaminophen, Chlorpheniramine Maleate, Dextromethorphan HBr 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 Hemp
Top 25%

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

29 days ago today
Medication Acetaminophen, Chlorpheniramine Maleate, Dextromethorphan HBr
Top 10%

#160 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 Hemp

What is Hemp?

Hemp
  • Plant-based protein source
  • Heart health support
  • Skin and hair health
  • Reducing inflammation
  • General nutrition (omega fatty acids)

Hemp seeds and hemp seed oil are nutritious foods rich in protein, fiber, and healthy omega-3 and omega-6 fatty acids, and they are generally safe for most people as part of the diet. While the nutrition is real, strong human evidence that hemp supplements treat specific medical conditions is limited. Talk with your pharmacist or doctor before using hemp products for a health concern, especially if you are pregnant or breastfeeding.

Read the full Hemp monograph & all interactions
Keep checking

Other Drugs & Hemp

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

0Major
41Moderate
898Minor
1,890No known interaction
Moderate

41 interactions

Minor

898 interactions

Showing 60 of 898 minor interactions — see all 898 on the Hemp page.

No interaction 1,890 drugs checked — show the list

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

Showing the 60 most looked-up of 1,890 medications checked with no known interaction — see the full Hemp 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 Hemp and Acetaminophen, Chlorpheniramine Maleate, Dextromethorphan HBr Together: Common Questions

Can you take Hemp with Acetaminophen, Chlorpheniramine Maleate, Dextromethorphan HBr?
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 Hemp and Acetaminophen, Chlorpheniramine Maleate, Dextromethorphan HBr?
Acetaminophen, Chlorpheniramine Maleate, Dextromethorphan HBr belongs to more than one drug category, and Hemp 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 Hemp and Acetaminophen, Chlorpheniramine Maleate, Dextromethorphan HBr 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

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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.