Drug & supplement interaction

Hu Zhang + Chlorpheniramine, Phenylpropanolamine

Chlorpheniramine, Phenylpropanolamine brand names: Ornade, Dehist, Conex DA, Histabid Duracaps, Contac, and others.

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

Hu Zhang has a moderate interaction with Chlorpheniramine, Phenylpropanolamine. Theoretically, hu zhang might increase levels of drugs metabolized by CYP3A4.

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

Hu Zhang and Chlorpheniramine, Phenylpropanolamine

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

Moderate

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES

Why this applies to Chlorpheniramine, Phenylpropanolamine

Chlorpheniramine, Phenylpropanolamine falls under CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES — the group Hu Zhang interacts with.

Theoretically, hu zhang might increase levels of drugs metabolized by CYP3A4.
Hu zhang contains the constituent resveratrol. In vitro research shows that resveratrol might inhibit the CYP3A4 enzyme. However, a clinical study in adults with NAFLD found that adding resveratrol 3000 mg daily for 8 weeks did not necessitate dose adjustments to any established medications metabolized by CYP3A4.
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 this combo. Hu Zhang is rich in resveratrol, and in test-tube studies resveratrol can slow down CYP3A4, one of the liver enzymes that helps clear the chlorpheniramine (the antihistamine) portion of this product. If that enzyme runs slower, the drug could linger a bit longer and you might feel its effects more strongly, things like drowsiness, dry mouth, blurred vision, or feeling foggy.

That said, this is mostly a theoretical concern. A human study using a large 3000 mg daily dose of resveratrol didn't force any dose changes for CYP3A4 medicines, so the real-world risk looks small. Still, the phenylpropanolamine here is a stimulant decongestant, so if you notice jitteriness, a racing heart, or extra sleepiness, check in with your pharmacist or doctor.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Piver B, Berthou F, Dreano Y, Lucas D. Inhibition of CYP3A, CYP1A and CYP2E1 activities by resveratrol and other non volatile red wine components. Toxicol Lett 2001;125:83-91. PubMed
  2. Yu, C., Shin, Y. G., Kosmeder, J. W., Pezzuto, J. M., and van Breemen, R. B. Liquid chromatography/tandem mass spectrometric determination of inhibition of human cytochrome P450 isozymes by resveratrol and resveratrol-3-sulfate. Rapid Commun.Mass Spectro PubMed
  3. Chachay VS, Macdonald GA, Martin JH, Whitehead JP, O'Moore-Sullivan TM, Lee P, Franklin M, Klein K, Taylor PJ, Ferguson M, Coombes JS, Thomas GP, Cowin GJ, Kirkpatrick CM, Prins JB, Hickman IJ. Resveratrol does not benefit patients with nonalcoholic fatty

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

Hu Zhang Also Interacts With Other Medications

Hu Zhang has 827 moderate known drug interactions in our database — the Chlorpheniramine, Phenylpropanolamine one above is one of them. If you take anything else, check it against the full list below.

Moderate 827 No known interaction 2,003 (incl. Chlorpheniramine, Phenylpropanolamine)
Taking anything else?

Check Another of Your Medications Against Hu Zhang

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

Everything else you take

See Every Supplement That Interacts With Chlorpheniramine, Phenylpropanolamine

This page covers Hu Zhang only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Chlorpheniramine, Phenylpropanolamine page lists 229 supplements it has a documented interaction with, worst first, each one explained.

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

By severity: 10 major · 175 moderate · 44 minor.

From our pharmacist’s overview on the Chlorpheniramine, Phenylpropanolamine page

“Chlorpheniramine with phenylpropanolamine (Contac, Ornade, Dehist) is an older allergy pill paired with a decongestant, and its supplement list deserves genuine care, with the ten major-rated entries the ones to understand first. The biggest cluster changes how the body clears the drug: grapefruit can drive its levels up, while St.”

Reviewed by 2 · Jul 18, 2026

Open the Chlorpheniramine, Phenylpropanolamine interaction page

One more smart check

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

We hold 1,014 real supplement products containing Hu Zhang, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Hu Zhang. Your product may carry other ingredients that interact with Chlorpheniramine, Phenylpropanolamine too, on top of Hu Zhang — 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 Hu Zhang and Chlorpheniramine, Phenylpropanolamine 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 Hu Zhang
Top 25%

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

29 days ago today
Medication Chlorpheniramine, Phenylpropanolamine
Top half

#1,403 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 Hu Zhang

What is Hu Zhang?

  • Source of resveratrol
  • Heart and circulation support
  • Inflammation
  • Liver and digestive complaints (traditional)
  • Cough and respiratory symptoms (traditional)
  • Skin and joint conditions (traditional topical use)

Hu Zhang (Japanese knotweed root) is a traditional Chinese herb that is one of the richest natural sources of resveratrol and emodin. Some lab and early human research looks interesting for inflammation and heart health, but high-quality evidence in people is limited. Talk to your pharmacist or doctor before using it, and avoid it during pregnancy and breastfeeding.

Read the full Hu Zhang monograph & all interactions
Keep checking

Other Drugs & Hu Zhang

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

0Major
827Moderate
0Minor
2,002No known interaction
827 Moderate 2,002 No interaction
Moderate

827 interactions

Showing 60 of 827 moderate interactions — see all 827 on the Hu Zhang page.

No interaction 2,002 drugs checked — show the list

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

Showing the 60 most looked-up of 2,002 medications checked with no known interaction — see the full Hu Zhang list.

See the full Hu Zhang interactions page
See every supplement checked against Chlorpheniramine, Phenylpropanolamine, 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
Hu Zhang monograph › Uses, safety, and every drug interaction in one place Chlorpheniramine, Phenylpropanolamine supplement interactions › Every supplement checked against Chlorpheniramine, Phenylpropanolamine, 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 Hu Zhang and Chlorpheniramine, Phenylpropanolamine Together: Common Questions

Can you take Hu Zhang with Chlorpheniramine, Phenylpropanolamine?
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 Hu Zhang and Chlorpheniramine, Phenylpropanolamine 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 Chlorpheniramine, Phenylpropanolamine and Hu Zhang?

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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.