Drug & supplement interaction

Hemp Agrimony + Aspirin, Codeine Phosphate, Phenobarbital

Aspirin, Codeine Phosphate, Phenobarbital brand name: Phenaphen.

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

Hemp Agrimony has a moderate interaction with Aspirin, Codeine Phosphate, Phenobarbital. Hemp agrimony contains hepatotoxic pyrrolizidine alkaloids (PA) which are substrates of cytochrome P450 3A4 (CYP3A4).

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

Hemp Agrimony and Aspirin, Codeine Phosphate, Phenobarbital

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

Moderate

CYTOCHROME P450 3A4 (CYP3A4) INDUCERS

Why this applies to Aspirin, Codeine Phosphate, Phenobarbital

Aspirin, Codeine Phosphate, Phenobarbital falls under CYTOCHROME P450 3A4 (CYP3A4) INDUCERS — the group Hemp Agrimony interacts with.

Hemp agrimony contains hepatotoxic pyrrolizidine alkaloids (PA) which are substrates of cytochrome P450 3A4 (CYP3A4). Theoretically, drugs that induce CYP3A4 might increase the conversion of PAs to toxic metabolites. Some drugs that induce CYP3A4 include carbamazepine (Tegretol), phenobarbital, phenytoin (Dilantin), rifampin, rifabutin (Mycobutin), and others.
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 key thing about this combination product (aspirin, codeine, and phenobarbital): it's the phenobarbital piece that matters. Phenobarbital is a strong inducer, meaning it revs up a liver enzyme called CYP3A4. Hemp agrimony naturally contains pyrrolizidine alkaloids, which can be hard on the liver, and that same enzyme can turn those compounds into more toxic byproducts. So in theory, taking them together could speed up the conversion of those plant chemicals into something more damaging to your liver.

I want to be honest about the strength of this concern. It's based on lab work, not real people, so it's more of a theoretical caution. That said, hemp agrimony is already discouraged for internal use because of liver risk. Please don't start it without checking with your pharmacist or doctor first.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Chojkier M. Hepatic sinusoidal-obstruction syndrome: toxicity of pyrrolizidine alkaloids. J Hepatol 2003;39:437-46. PubMed
  2. Wang YP, Yan J, Fu PP, Chou MW. Human liver microsomal reduction of pyrrolizidine alkaloid N-oxides to form the corresponding carcinogenic parent alkaloid. Toxicol Lett 2005;155:411-20. 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 Agrimony Also Interacts With Other Medications

Hemp Agrimony has 437 moderate known drug interactions in our database — the Aspirin, Codeine Phosphate, Phenobarbital one above is one of them. If you take anything else, check it against the full list below.

Moderate 437 No known interaction 2,393 (incl. Aspirin, Codeine Phosphate, Phenobarbital)
Taking anything else?

Check Another of Your Medications Against Hemp Agrimony

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

Everything else you take

See Every Supplement That Interacts With Aspirin, Codeine Phosphate, Phenobarbital

This page covers Hemp Agrimony only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Aspirin, Codeine Phosphate, Phenobarbital page lists 352 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 Danshen (major).

By severity: 12 major · 304 moderate · 36 minor.

From our pharmacist’s overview on the Aspirin, Codeine Phosphate, Phenobarbital page

“Alcohol is the entry I would flag first with Phenaphen (aspirin, codeine phosphate, phenobarbital): beer or wine layered onto codeine and phenobarbital can deepen sedation and, at worst, slow breathing. This medication deserves real caution with supplements.”

Reviewed by 2 · Jul 18, 2026

Open the Aspirin, Codeine Phosphate, Phenobarbital interaction page

One more smart check

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

We hold 3 real supplement products containing Hemp Agrimony, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Hemp Agrimony. Your product may carry other ingredients that interact with Aspirin, Codeine Phosphate, Phenobarbital too, on top of Hemp Agrimony — 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 Agrimony and Aspirin, Codeine Phosphate, Phenobarbital 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 Agrimony
Steady interest

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

29 days ago today
Medication Aspirin, Codeine Phosphate, Phenobarbital
Top 10%

#209 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 Agrimony

What is Hemp Agrimony?

Hemp Agrimony
  • Digestive complaints
  • Cold and flu symptoms
  • Respiratory conditions
  • Mild fever
  • Traditional 'tonic' or detox use

Hemp agrimony is a traditional European herb that has been used for digestion, colds, and as a general tonic, but there is very little reliable human research to support these uses. More importantly, the plant can contain pyrrolizidine alkaloids that may harm the liver, so most experts do not recommend taking it internally. Talk with your pharmacist or doctor before using any product that contains hemp agrimony.

Read the full Hemp Agrimony monograph & all interactions
Keep checking

Other Drugs & Hemp Agrimony

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

0Major
437Moderate
0Minor
2,392No known interaction
437 Moderate 2,392 No interaction
Moderate

437 interactions

Showing 60 of 437 moderate interactions — see all 437 on the Hemp Agrimony page.

No interaction 2,392 drugs checked — show the list

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

Showing the 60 most looked-up of 2,392 medications checked with no known interaction — see the full Hemp Agrimony list.

See the full Hemp Agrimony interactions page
See every supplement checked against Aspirin, Codeine Phosphate, Phenobarbital, 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
Hemp Agrimony monograph › Uses, safety, and every drug interaction in one place Aspirin, Codeine Phosphate, Phenobarbital supplement interactions › Every supplement checked against Aspirin, Codeine Phosphate, Phenobarbital, 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 Hemp Agrimony and Aspirin, Codeine Phosphate, Phenobarbital Together: Common Questions

Can you take Hemp Agrimony with Aspirin, Codeine Phosphate, Phenobarbital?
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.
How serious is the Hemp Agrimony and Aspirin, Codeine Phosphate, Phenobarbital 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 Aspirin, Codeine Phosphate, Phenobarbital and Hemp Agrimony?

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.