Drug & supplement interaction

Poria Mushroom + Chlorpheniramine, Phenylephrine

Chlorpheniramine, Phenylephrine brand names: Histatab Plus, Ed A Hist, Rynatan, Dallergy JR.

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

Poria Mushroom has a moderate interaction with Chlorpheniramine, Phenylephrine. Theoretically, poria mushroom might decrease the clinical effects of anticholinergic drugs.

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

Poria Mushroom and Chlorpheniramine, Phenylephrine

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

Moderate

ANTICHOLINERGIC DRUGS

Why this applies to Chlorpheniramine, Phenylephrine

Chlorpheniramine, Phenylephrine falls under ANTICHOLINERGIC DRUGS — the group Poria Mushroom interacts with.

Theoretically, poria mushroom might decrease the clinical effects of anticholinergic drugs.
In animal research, poria mushroom essential oil reduces acetylcholinesterase activity. This interaction has not been shown in humans.
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 for your cold and allergy combo. The chlorpheniramine part works partly by blocking acetylcholine, one of the body's signaling chemicals. In animal studies, poria mushroom seems to keep more acetylcholine around. In theory, that extra acetylcholine could push back against chlorpheniramine and slightly soften its effects, so your sneezing, runny nose, or itchy eyes might not calm down quite as well.

Keep this in perspective. This is only a lab-and-animal idea, and it has never been shown to actually happen in people. The phenylephrine (decongestant) side isn't really involved here. I wouldn't lose sleep over it, but since both can affect how you feel, just run it past your pharmacist or doctor before combining them.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Lv Q, Di X, Bian B, Li K, Guo J. Neuroprotective effects of Poria cocos (Agaricomycetes) essential oil on Aß1-40-induced learning and memory deficit in rats. Int J Med Mushrooms 2022;24(10):73-82.

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

Poria Mushroom Also Interacts With Other Medications

Poria Mushroom has 416 moderate known drug interactions in our database — the Chlorpheniramine, Phenylephrine one above is one of them. If you take anything else, check it against the full list below.

Moderate 416 No known interaction 2,414 (incl. Chlorpheniramine, Phenylephrine)
Taking anything else?

Check Another of Your Medications Against Poria Mushroom

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

Everything else you take

See Every Supplement That Interacts With Chlorpheniramine, Phenylephrine

This page covers Poria Mushroom only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Chlorpheniramine, Phenylephrine 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, Phenylephrine page

“A medicine that stimulates the heart and dries the body doesn't leave much room for supplements pulling the same way, and that describes chlorpheniramine, phenylephrine (Histatab Plus, Ed A Hist, Rynatan) well. Dozens of stimulant herbs, everyday caffeine sources among them, add to the decongestant's strain on blood pressure and heart…”

Reviewed by 2 · Jul 18, 2026

Open the Chlorpheniramine, Phenylephrine interaction page

One more smart check

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

We hold 1,303 real supplement products containing Poria Mushroom, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Poria Mushroom. Your product may carry other ingredients that interact with Chlorpheniramine, Phenylephrine too, on top of Poria Mushroom — 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 Poria Mushroom and Chlorpheniramine, Phenylephrine 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 Poria Mushroom
Top 25%

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

29 days ago today
Medication Chlorpheniramine, Phenylephrine
Steady interest

#1,526 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 Poria Mushroom

What is Poria Mushroom?

  • Fluid retention and swelling
  • Digestive complaints
  • Sleep and calming support
  • General wellness and immune support
  • Urinary support

Poria mushroom (Fu Ling) is a fungus long used in Traditional Chinese Medicine, mainly as a mild diuretic and digestive and calming aid. Modern scientific evidence in humans is very limited, so its benefits are not well proven. It is generally considered well tolerated, but talk with your pharmacist or doctor before using it, and avoid it in pregnancy and breastfeeding due to a lack of safety data.

Read the full Poria Mushroom monograph & all interactions
Keep checking

Other Drugs & Poria Mushroom

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

0Major
416Moderate
0Minor
2,413No known interaction
416 Moderate 2,413 No interaction
Moderate

416 interactions

Showing 60 of 416 moderate interactions — see all 416 on the Poria Mushroom page.

No interaction 2,413 drugs checked — show the list

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

Showing the 60 most looked-up of 2,413 medications checked with no known interaction — see the full Poria Mushroom list.

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

Can you take Poria Mushroom with Chlorpheniramine, Phenylephrine?
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 Poria Mushroom and Chlorpheniramine, Phenylephrine 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, Phenylephrine and Poria Mushroom?

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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.