Drug & supplement interaction

Roman Chamomile + 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 Roman Chamomile 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. Additionally, although there is no interaction, the two are separately associated with some of the same side effects, which would make a new symptom harder to attribute to one or the other.

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Interaction report

Roman Chamomile 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 Roman Chamomile 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.

Worth understanding: our licensed dataset holds no drug-interaction record for Roman Chamomile at all — not against Phenylephrine, and not against any other medication we track. This verdict therefore rests on the absence of any recorded data, not on research that looked at this combination and found nothing. We cannot rule an interaction out.

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.

Roman Chamomile safety at a glance

Roman Chamomile overall Use caution Generally well tolerated in tea or food amounts, but allergic reactions are possible in sensitive people.
Pregnancy Likely Unsafe When used orally in medicinal amounts. Roman chamomile is believed to be an abortifacient. Some population research has found a possible link between the use of... Read the full pregnancy detail
Breastfeeding Use caution Not enough reliable safety data, so use caution and ask your doctor first.

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 Roman Chamomile? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
What to actually watch for

No Interaction Found — But Data Suggests Roman Chamomile and Phenylephrine May Share a Side Effect

This is not an interaction. Neither one changes how your body handles the other, and nothing here says they react together. What our sources do show is that each has separately been linked to the effects below — so taking both can make those effects more likely to turn up, and harder to pin on one or the other if they do.

  • Vomiting Additional detail

    Roman Chamomile

    “Orally, large amounts of Roman chamomile might cause vomiting, although data are conflicting (11,12).”

    Roman Chamomile · Natural Medicines adverse-effect record, reported in nausea and vomiting.

    2 sources cited
    1. 11. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
    2. 12. McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.

    Phenylephrine

    Listed in the ADVERSE REACTIONS section of the FDA label for Phenylephrine. Read the label on DailyMed ›

Reported for Roman Chamomile but not commonly for Phenylephrine: an allergic reaction, a skin rash, a stuffy or runny nose and cough.

Effects for Phenylephrine come from the ADVERSE REACTIONS section of its FDA label; effects for Roman Chamomile come from the Natural Medicines adverse-effect record, quoted above. Where a percentage is shown, it is the share of 221,388 voluntary FDA FAERS reports for Phenylephrine that mention that effect — a reporting proportion, not an incidence rate and not evidence the drug caused it. Wording is matched across sources by our own clinical vocabulary, so treat this as a prompt to pay attention, not a diagnosis.

Special populations

Roman Chamomile in Pregnancy & Breastfeeding

Pregnancy Likely Unsafe

When used orally in medicinal amounts. Roman chamomile is believed to be an abortifacient. Some population research has found a possible link between the use of Roman chamomile and an increased incidence of reduced birth weight, threatened miscarriage, and preterm labor. There is insufficient reliable information available about the safety of the topical use of Roman chamomile during pregnancy; avoid using.

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

Overlapping uses

What Phenylephrine Is Prescribed For, and What Roman Chamomile Has Been Studied For

These two come up together because they touch the same health topic — not because they do the same job. Phenylephrine is a prescription medicine with approved uses on its FDA label. Roman Chamomile is a supplement: what follows is what researchers have looked at it for, and how strong that evidence is.

Phenylephrine is prescribed for: 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.

Read the rest of what Phenylephrine is prescribed for

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.

Roman Chamomile has been studied for:

  • Hemorrhoids studied, not established Roman Chamomile has been studied for this. Natural Medicines rates the evidence: Insufficient Reliable Evidence To Rate Read what the research shows

    Roman Chamomile for hemorrhoids

    Although there is interest in using topical Roman chamomile for hemorrhoids, there is insufficient reliable information about the clinical effects of Roman chamomile for this purpose.

Effectiveness ratings and the research summaries above are the verbatim record from the Natural Medicines database, which grades evidence from “Effective” down to “Insufficient Reliable Evidence To Rate”. A rating below the top of that scale means researchers have looked at it — not that it works, and never that it can stand in for a prescribed medicine. Do not stop or replace Phenylephrine on your own; if you are taking Roman Chamomile for the same health topic, tell your prescriber, especially if the medicine is being adjusted to a target.

From our Q&A

Questions About Roman Chamomile 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 Roman Chamomile 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 Roman Chamomile 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

One more smart check

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

We hold 8 real supplement products containing Roman Chamomile, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Roman Chamomile. Even though Roman Chamomile itself has no known interaction with Phenylephrine, another ingredient on your label might. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Roman Chamomile 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 Roman Chamomile
Steady interest

#1,052 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Phenylephrine
Top 25%

#444 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 Roman Chamomile reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified October 4, 2026. The Roman Chamomile 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 Roman Chamomile

What is Roman Chamomile?

  • Digestive upset
  • Anxiety and relaxation
  • Sleep support
  • Skin irritation
  • Menstrual cramps

Roman chamomile is a daisy-family herb used traditionally as a calming tea and as an oil for digestion, mild anxiety, and skin comfort. Solid human evidence is limited for most uses, but it is generally considered safe in food and tea amounts for most adults. People allergic to ragweed and related plants should be cautious, and pregnant or breastfeeding people should check with a doctor first.

Chamaemelum nobile · Asteraceae · Flowers (and essential oil) · Tea, capsules, liquid extract, essential oil, topical creams

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

Roman Chamomile: dosing

There is no official standardized dose for Roman chamomile. The amount varies widely depending on the product and the form (tea, capsule, or extract).A common traditional use is one cup of chamomile tea made from the dried flowers, taken up to a few times a day. For capsules or liquid extracts, follow the directions on the product label, since strengths differ between brands.

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

Read the full Roman Chamomile 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 & Roman Chamomile

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

0Major
0Moderate
0Minor
2,829No known interaction
No interaction 2,829 drugs checked — show the list
Evidence & sources

Roman Chamomile References

The 6 references that drive our Roman Chamomile 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. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
  3. McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
  4. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
  5. Subiza J, Subiza JL, Hinojosa M, et al. Anaphylactic reaction after the ingestion of chamomile tea; a study of cross-reactivity with other composite pollens. J Allergy Clin Immunol 1989;84:353-8. PubMed
  6. Sharma AK, Basu I, Singh S. Efficacy and safety of Ashwagandha root extract in subclinical hypothyroid patients: a double-blind, randomized placebo-controlled trial. J Altern Complement Med. 2018 Mar;24(3):243-248. 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 Roman Chamomile and Phenylephrine Together: Common Questions

Is it safe to take Roman Chamomile with Phenylephrine?
We do not list a known interaction between Roman Chamomile 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.
Do Roman Chamomile and Phenylephrine have any of the same side effects?
Yes — our sources link each of them separately to one of the same effects. That is not an interaction: neither changes how your body handles the other. It does mean that if one of those effects turns up, it can be harder to tell which one is behind it. They are listed on this page with the source behind each.
Are Roman Chamomile and Phenylephrine used for the same thing?
They overlap in purpose, which usually means the real question is whether you need both rather than whether they are safe together. This page lists the shared uses and how strong the evidence is for Roman Chamomile in each. That is a conversation for your prescriber, especially if Phenylephrine is being adjusted to a target.
Does Phenylephrine interact with any supplements?
Yes. Phenylephrine has documented interactions with 81 supplements in our database — Roman Chamomile 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 Roman Chamomile?

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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.