Drug & supplement interaction

Great Plantain + Phenylephrine

Phenylephrine brand names: Gilchew, AH Chew D, Gilchew IR, Sudafed PE, Biorphen.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Great Plantain and Phenylephrine in our sources. Absence of a documented interaction is not the same as proven safety, and does not guarantee one does not exist. Do not start, stop, or change a medication or supplement based on this page; confirm with your pharmacist or doctor first.

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Interaction report

Great Plantain and Phenylephrine

We checked these two against our interaction database. Here is what we found.

No Known Interaction Found

We did not find a documented interaction between Phenylephrine and Great Plantain in our sources. This does not guarantee that the combination is completely free of risk — there is often limited research on supplements and herbal products, especially around drug interactions.

If you decide to take both, the practical routine is simple: add one new thing at a time and note the date you started it. If the combination is going to disagree with you, it usually shows in the first days to a couple of weeks — and a start date turns “I’ve been feeling off” into something a pharmacist can actually work with. Do not stop a prescribed medicine on your own.

Always talk with your pharmacist or doctor before making changes to your medications or supplements, particularly if you take several medications or have an ongoing health condition.

Great Plantain safety at a glance

Great Plantain overall Use caution Generally considered well tolerated for most adults, but human safety data are limited.
Pregnancy Likely Unsafe When used orally because it can increase uterine tone. Read the full pregnancy detail
Breastfeeding Avoid Safety while breastfeeding is unknown, so avoid medicinal amounts.

Pregnancy & breastfeeding ratings are from Natural Medicines (Therapeutic Research Center) — the full detail is in the Special populations card below. Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Phenylephrine and Great Plantain? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Phenylephrine

Interactions in our licensed database are recorded against drug classes, not just single drug names. Phenylephrine is filed under 5 classifications — including alpha-adrenergic agonists, stimulant drugs, serotonergic drugs. Great Plantain has documented interactions with 1 drug class — the most serious being warfarin (coumadin) (moderate) — and none of Phenylephrine’s classifications are among them.

Classification data comes from our licensed Natural Medicines dataset. A medication can belong to classes beyond those recorded there, so this describes how the check was run — it is not a safety guarantee.

Keep it in perspective

Great Plantain Does Interact With Other Medications

Great Plantain has 2 moderate known drug interactions in our database — Phenylephrine isn’t one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Great Plantain

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

What to actually watch for

What Great Plantain Itself Has Been Linked To

This is not an interaction — nothing below involves Phenylephrine. It is the side-effect record for Great Plantain on its own, from the licensed Natural Medicines monograph. If something new turns up after you add Great Plantain, this list is the first place to look.

  • A skin rash Additional detail

    “Topically, application can cause allergic contact dermatitis in some individuals (4).”

    Great Plantain · Natural Medicines adverse-effect record, reported in dermatitis.

    1 source cited
    1. 4. Newall CA, Anderson LA, Philpson JD. Herbal Medicine: A Guide for Healthcare Professionals. London, UK: The Pharmaceutical Press, 1996.

Everything above comes from the Natural Medicines adverse-effect record for Great Plantain — expand a row for the licensed statement it rests on. We read the ADVERSE REACTIONS section of Phenylephrine’s FDA label too, and the two lists don’t meaningfully overlap — which is why no Phenylephrine column appears here.

Special populations

Great Plantain in Pregnancy & Breastfeeding

Pregnancy Likely Unsafe

When used orally because it can increase uterine tone.

DISCLAIMER: This tool is intended for informational purposes only, and should not be interpreted as specific medical advice. Patients should consult with a qualified healthcare provider before making decisions about therapies and/or health conditions.© 2026 Therapeutic Research Center

From our Q&A

Questions About Great Plantain or Phenylephrine

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Great Plantain or Phenylephrine, not necessarily both, but if one is close to what you were about to ask it will usually go further than a database entry can:

Not quite your question? Ask our pharmacists directly — it is free, there is no account required, and answers usually come back within 24 hours.

Everything else you take

See Every Supplement That Interacts With Phenylephrine

This page covers Great Plantain only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Phenylephrine page lists 81 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Ephedra (major), Lithium (major), Peyote (major) and Rauvolfia Vomitoria (major).

By severity: 6 major · 60 moderate · 15 minor.

From our pharmacist’s overview on the Phenylephrine page

“If you take phenylephrine (Sudafed PE, Biorphen) for congestion, treat this list as one that needs real attention, since six of its 81 entries carry a major rating. Phenylephrine tightens blood vessels to clear your nose, and more than half of the interactions here come from stimulant ingredients, ephedra above all, that can push blood…”

Reviewed by 2 · Jul 18, 2026

Open the Phenylephrine interaction page

How much people look this up

Where Great Plantain and 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 Great Plantain
Steady interest

#1,218 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Phenylephrine
Top half

#749 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.

Where does our data come from?
  • Source: the Natural Medicines (TRC Healthcare) clinical database — the evidence-graded professional reference for herb & supplement interactions.
  • Citation library: 103,510 references behind our interaction content, 65,311 of them resolved to verified PubMed/DOI sources. See every Great Plantain reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified October 4, 2026. The Great Plantain and Phenylephrine records this page draws on were last updated July 11, 2026.
  • What “no known interaction” means: no documented interaction in the sources above — not a guarantee of safety. Supplements are studied far less than prescription drugs, so we say exactly what the evidence supports, and nothing more.
Data structure & sourcing designed and verified by .
Supplement

About Great Plantain

What is Great Plantain?

  • Minor wounds and skin irritation
  • Insect bites and stings
  • Coughs and sore throat
  • Digestive upset
  • Mild inflammation

Great Plantain is a common weed traditionally used on the skin for minor wounds and bites, and as a tea for coughs or stomach upset. Human evidence for most of these uses is limited, though the plant appears generally well tolerated. Talk with your pharmacist or doctor before using it, especially if you are pregnant, breastfeeding, or have a health condition.

Plantago major · Plantaginaceae · Leaves and seeds · Tea, capsules, tinctures, topical salves and ointments, fresh crushed leaves (poultice)

An interaction check asks whether these two react with each other — it does not ask whether Great Plantain is a good idea for someone in your situation. Here is what our Great Plantain record says about it on its own.

Great Plantain: dosing

There is no well-established standardized dose for Great Plantain. Traditional use varies widely, and the amount of active compounds differs between products and plant sources.If you choose to use it, follow the directions on the product label and do not exceed the recommended amount. A pharmacist or doctor can help you decide whether it is appropriate for you and review your other medications and health conditions first.

From our Great Plantain monograph — the full record covers uses, side effects and every documented interaction.

Read the full Great Plantain monograph & all interactions
Medication

About Phenylephrine

What Is Phenylephrine Used For?

Brand names: Gilchew, AH Chew D, Gilchew IR, Sudafed PE, Biorphen

Phenylephrine is used in several different products, and each one has its own use.

Injection (IV): raises blood pressure in adults with clinically important hypotension (low blood pressure) caused mainly by widened blood vessels. Some injections are labeled for anesthesia only. Others are labeled for anesthesia and septic shock.

Eye drops: Phenylephrine Hydrochloride Ophthalmic Solution is used to dilate the pupil.

Nasal products: temporarily relieve nasal and sinus congestion from the common cold, hay fever or other upper respiratory allergies.

Rectal suppositories: relieve itching, burning and discomfort from hemorrhoids and temporarily shrink hemorrhoidal tissue.

Most-Reported Side Effects for Phenylephrine

From FAERS, the FDA’s public side-effect reporting system (221,388 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Fatigue 20,609 reports
Headache 17,301 reports
Nausea 16,925 reports
Diarrhea 14,221 reports
Dyspnea 13,719 reports
See full Phenylephrine drug information
Keep checking

Other Drugs & Great Plantain

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

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

2 interactions

No interaction 2,827 drugs checked — show the list
Evidence & sources

Great Plantain References

The 3 references that drive our Great Plantain monograph and interaction data, from the evidence-graded Natural Medicines (TRC Healthcare) database. Citations with a link open the study on PubMed or the publisher’s site.

  1. Newall CA, Anderson LA, Philpson JD. Herbal Medicine: A Guide for Healthcare Professionals. London, UK: The Pharmaceutical Press, 1996.
  2. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
  3. Adom MB, Taher M, Mutalabisin MF, et al. Chemical constituents and medical benefits of Plantago major. Biomed Pharmacother. 2017;96:348-360. PubMed

Medication overviews come from MedlinePlus (NIH); supplement label data from the NIH Dietary Supplement Label Database. Content is written and reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.

Pharmacist Counseling Corner

Taking Great Plantain and Phenylephrine Together: Common Questions

Is it safe to take Great Plantain with Phenylephrine?
We do not list a known interaction between Great Plantain and Phenylephrine. That does not guarantee the combination is risk-free, so confirm with your pharmacist or doctor — especially if you take other medications or have a health condition.
How was the Great Plantain and Phenylephrine combination checked?
Interactions in our licensed database are recorded against drug classes. Phenylephrine is filed under 5 classifications, and Great Plantain has documented interactions with 1 drug class — none of Phenylephrine's classifications are among them. A medication can belong to classes beyond those recorded in our dataset, so this describes how the check was run rather than guaranteeing safety.
Does Great Plantain interact with any other medications?
Yes. Great Plantain has 2 documented drug interactions in our database — Phenylephrine is simply not one of them. If you take anything else, it is worth checking each one; they are all listed on this page.
Does Phenylephrine interact with any supplements?
Yes. Phenylephrine has documented interactions with 81 supplements in our database — Great Plantain is not one of them. The Phenylephrine interaction page linked on this page lists every one, ranked by severity.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

Still Have a Question About Phenylephrine and Great Plantain?

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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.