Drug & supplement interaction

Schizonepeta + Acetaminophen, Pseudoephedrine

Acetaminophen, Pseudoephedrine brand names: Sinutab, Tylenol Sinus, Sudafed Sinus, Tylenol Sinus Ex Strength, Children's Tylenol Sinus, and others.

Moderate Interaction
The bottom line Moderate

Acetaminophen, Pseudoephedrine falls into 2 drug categories that Schizonepeta can interact with; the most serious is rated moderate. Animal research suggests that schizonepetin, a monoterpene constituent of schizonepeta, inhibits cytochrome P450 (CYP) 1A2.

Read the full interaction report
SeverityModerate
LikelihoodPossible
Interactions2
EvidenceD
What do Severity, Likelihood & Evidence mean?
Know someone taking this? Share
Interaction report

Schizonepeta and Acetaminophen, Pseudoephedrine

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

Why Are There 2 Interactions?

Schizonepeta interacts with whole categories of medication. Acetaminophen, Pseudoephedrine falls into 2 of those categories, so it can interact with Schizonepeta 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, Pseudoephedrine

Acetaminophen, Pseudoephedrine falls under CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES — the group Schizonepeta interacts with.

Animal research suggests that schizonepetin, a monoterpene constituent of schizonepeta, inhibits cytochrome P450 (CYP) 1A2. Theoretically, schizonepeta might increase the effects and side effects of CYP1A2 substrates.
Some substrates of CYP1A2 include clozapine (Clozaril), cyclobenzaprine (Flexeril), fluvoxamine (Luvox), haloperidol (Haldol), imipramine (Tofranil), mexiletine (Mexitil), olanzapine (Zyprexa), pentazocine (Talwin), propranolol (Inderal), tacrine (Cognex), theophylline, zileuton (Zyflo), zolmitriptan (Zomig), 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 honest picture: this concern comes from lab and animal work showing a compound in Schizonepeta may slow down a liver enzyme called CYP1A2. The thinking is that if a drug leans on that enzyme to be cleared, it could build up a bit and bring stronger effects. With your sinus combo, neither acetaminophen (Tylenol) nor pseudoephedrine (Sudafed) really depends on CYP1A2 in a major way, so any real-world impact is likely small.

Still, keep an eye out for the usual pseudoephedrine effects if you stack them, things like jitteriness, a racing heart, trouble sleeping, or a bump in blood pressure. Since this is only theoretical and based on animal data, I wouldn't lose sleep over it, but do run it by your pharmacist if you take Schizonepeta regularly.

References
  1. Bao B, Geng T, Cao Y, et al. Effects of schizonepetin on activity of mRNA expression of cytochrome P450 enzymes in rats. Int J Mol Sci. 2012;13(12):17006-18.
Moderate

CYTOCHROME P450 2E1 (CYP2E1) SUBSTRATES

2 of 2

Acetaminophen, Pseudoephedrine also falls under CYTOCHROME P450 2E1 (CYP2E1) SUBSTRATES.

Animal research suggests that schizonepetin, a monoterpene constituent of schizonepeta, inhibits cytochrome P450 (CYP) 2E1. Theoretically, schizonepeta might increase the effects and side effects of CYP2E1 substrates.
Some substrates of CYP2E1 include acetaminophen, chlorzoxazone (Parafon Forte), ethanol, theophylline, and anesthetics such as enflurane (Ethrane), halothane (Fluothane), isoflurane (Forane), and methoxyflurane (Penthrane).
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 short version on this combo. The acetaminophen part of your Tylenol Sinus is partly handled by a liver enzyme called CYP2E1. In lab and animal studies, a compound in Schizonepeta appears to slow that enzyme down. In theory, slowing it could let a bit more acetaminophen linger in your body. The interesting twist is that CYP2E1 is the same pathway that turns acetaminophen into the byproduct that can stress the liver, so this isn't a clear-cut "more side effects" situation.

The honest truth is that this is only based on animal data, not people, so it's quite theoretical. The pseudoephedrine side isn't really involved here. Still, if you regularly take this herb, drink alcohol, or use acetaminophen often, mention it to your pharmacist so you stay within safe acetaminophen limits.

References
  1. Bao B, Geng T, Cao Y, et al. Effects of schizonepetin on activity of mRNA expression of cytochrome P450 enzymes in rats. Int J Mol Sci. 2012;13(12):17006-18.

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

Schizonepeta Also Interacts With Other Medications

Schizonepeta has 796 moderate known drug interactions in our database — the Acetaminophen, Pseudoephedrine 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 Schizonepeta

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

Everything else you take

See Every Supplement That Interacts With Acetaminophen, Pseudoephedrine

This page covers Schizonepeta only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Acetaminophen, Pseudoephedrine page lists 197 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), Ephedra (major) and Peyote (major).

By severity: 9 major · 149 moderate · 39 minor.

From our pharmacist’s overview on the Acetaminophen, Pseudoephedrine page

“Nine of the 197 supplement interactions on file for acetaminophen with pseudoephedrine (Tylenol Sinus, Sudafed Sinus, Sinutab) carry a major rating, so treat this page with genuine care before you pair the medicine with anything else. Two problems drive the list.”

Reviewed by 2 · Jul 18, 2026

Open the Acetaminophen, Pseudoephedrine interaction page

One more smart check

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

We hold 285 real supplement products containing Schizonepeta, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Schizonepeta. Your product may carry other ingredients that interact with Acetaminophen, Pseudoephedrine too, on top of Schizonepeta — 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 Schizonepeta and Acetaminophen, Pseudoephedrine 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 Schizonepeta
Top half

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

29 days ago today
Medication Acetaminophen, Pseudoephedrine
Top 5%

#92 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 Schizonepeta

What is Schizonepeta?

  • Common cold and early-stage fever
  • Itchy skin rashes and hives
  • Sore throat
  • Headache
  • Measles and other skin eruptions (traditional use)

Schizonepeta is a mint-family herb long used in traditional Chinese medicine, usually as part of combination formulas for colds, fevers, and itchy skin conditions. Modern human evidence is very limited, so its benefits are not well proven. Talk to a pharmacist or doctor before using it, especially if you are pregnant, breastfeeding, or taking other medicines.

Read the full Schizonepeta monograph & all interactions
Keep checking

Other Drugs & Schizonepeta

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

0Major
796Moderate
0Minor
2,033No known interaction
Moderate

796 interactions

Showing 60 of 796 moderate interactions — see all 796 on the Schizonepeta page.

No interaction 2,033 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

Keep exploring
Pharmacist Counseling Corner

Taking Schizonepeta and Acetaminophen, Pseudoephedrine Together: Common Questions

Can you take Schizonepeta with Acetaminophen, Pseudoephedrine?
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 Schizonepeta and Acetaminophen, Pseudoephedrine?
Acetaminophen, Pseudoephedrine belongs to more than one drug category, and Schizonepeta 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 Schizonepeta and Acetaminophen, Pseudoephedrine 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 Acetaminophen, Pseudoephedrine and Schizonepeta?

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.