Drug & supplement interaction

Pheasant's Eye + Losartan Potassium

Losartan Potassium brand name: Cozaar.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Pheasant's Eye and Losartan Potassium 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.

Know someone taking this? Share
Interaction report

Pheasant's Eye and Losartan Potassium

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 Losartan Potassium and Pheasant's Eye 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.

Pheasant's Eye safety at a glance

Pheasant's Eye overall Avoid The plant is poisonous and contains potent heart-affecting compounds with a very narrow safety margin.
Pregnancy Likely Unsafe When used orally for self-medication. Read the full pregnancy detail
Breastfeeding Likely Unsafe When used orally for self-medication. Read the full breastfeeding detail

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 Losartan Potassium and Pheasant's Eye? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Losartan Potassium

Interactions in our licensed database are recorded against drug classes, not just single drug names. Losartan Potassium is filed under 7 classifications — including angiotensin receptor blockers (arbs), cytochrome p450 2c9 (cyp2c9) substrates, antihypertensive drugs. Pheasant's Eye has documented interactions with 7 drug classes — the most serious being digoxin (lanoxin) (major), corticosteroids (moderate) and diuretic drugs (moderate) — and none of Losartan Potassium’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

Pheasant's Eye Does Interact With Other Medications

Pheasant's Eye has 1 major, 155 moderate known drug interactions in our database — Losartan Potassium 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 Pheasant's Eye

Covers the 2,830 medications we’ve checked against Pheasant's Eye. Pick one to open its full report.

What to actually watch for

No Interaction Found — But Data Suggests Pheasant's Eye and Losartan Potassium May Share Several of the Same Side Effects

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. One of them is worth acting on rather than waiting out — marked below.

  • An irregular heartbeat Worth acting on Additional detail

    Pheasant's Eye

    “Orally, pheasant's eye might be unsafe due to its cardiac glycoside constituents.

    Serious Adverse Effects (Rare):

    Orally: Theoretically, digitalis-like effects including cardiac arrhythmia, diarrhea, nausea, and vomiting.”

    Pheasant's Eye · Natural Medicines adverse-effect record, reported in arrhythmia.

    Losartan Potassium

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

  • Diarrhea / Nausea / Vomiting reported in 5.9% of FDA reports for Losartan Potassium Additional detail

    Pheasant's Eye

    “Orally, adverse effects may include diarrhea, nausea, and vomiting (2). Pheasant's eye contains cardiac glycosides and can cause serious adverse effects when used orally without appropriate medical supervision (18,512,104545).”

    Pheasant's Eye · Natural Medicines adverse-effect record, reported in diarrhea.

    4 sources cited
    1. 2. Blumenthal M, ed. The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. Trans. S. Klein. Boston, MA: American Botanical Council, 1998.
    2. 18. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.
    3. 512. Robbers JE, Tyler VE. Tyler's Herbs of Choice: The Therapeutic Use of Phytomedicinals. New York, NY: The Haworth Herbal Press, 1999.
    4. 104545. Shang X, Miao X, Yang F, et al. The genus Adonis as an important cardiac folk medicine: A review of the ethnobotany, phytochemistry and pharmacology. Front Pharmacol. 2019;10:25. PubMed

    Losartan Potassium

    Listed in the ADVERSE REACTIONS section of the FDA label for Losartan Potassium, and in voluntary FDA adverse-event reports. Read the label on DailyMed ›

Effects for Losartan Potassium come from the ADVERSE REACTIONS section of its FDA label; effects for Pheasant's Eye come from the Natural Medicines adverse-effect record, quoted above. Where a percentage is shown, it is the share of 89,498 voluntary FDA FAERS reports for Losartan Potassium 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

Pheasant's Eye in Pregnancy & Breastfeeding

Pregnancy And Lactation Likely Unsafe

When used orally for self-medication.

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 Losartan Potassium Is Prescribed For, and What Pheasant's Eye Has Been Studied For

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

Losartan Potassium is prescribed for: Losartan tablets — available as branded Cozaar and several generic products — are used to treat high blood pressure (hypertension) in adults and children 6 years and older. Lowering blood pressure reduces the risk of strokes and heart attacks. Losartan tablets are also used to reduce the risk of stroke in people with high blood pressure who also have left ventricular hypertrophy (an enlarged left side of the heart). Note: evidence suggests this stroke-risk benefit may not apply to Black patients.

Read the rest of what Losartan Potassium is prescribed for

Losartan tablets are additionally approved to protect the kidneys in people with type 2 diabetes, high blood pressure, and signs of kidney damage (diabetic nephropathy). Arbli, the oral suspension form, shares these same approved uses.

Pheasant's Eye has been studied for:

  • Heart failure studied, not established Pheasant's Eye has been studied for this. Natural Medicines rates the evidence: Insufficient Reliable Evidence To Rate Read what the research shows

    Pheasant's Eye for heart failure

    Although there has been interest in using oral pheasant's eye for heart failure, there is insufficient reliable information about the clinical effects of pheasant's eye 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 Losartan Potassium on your own; if you are taking Pheasant's Eye for the same health topic, tell your prescriber, especially if the medicine is being adjusted to a target.

From our Q&A

Questions About Pheasant's Eye or Losartan Potassium

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Pheasant's Eye or Losartan Potassium, 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 Losartan Potassium

This page covers Pheasant's Eye only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Losartan Potassium page lists 253 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), American Hellebore (major), American Mistletoe (major), Grapefruit (major) and St. John's Wort (major).

By severity: 6 major · 205 moderate · 42 minor.

From our pharmacist’s overview on the Losartan Potassium page

“Losartan potassium (Cozaar) treats high blood pressure, and this is a list to respect, because six of its 253 supplement interactions carry a major rating. Most entries do one of two things.”

Reviewed by 2 · Jul 18, 2026

Open the Losartan Potassium interaction page

How much people look this up

Where Pheasant's Eye and Losartan Potassium 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 Pheasant's Eye
Steady interest

#1,433 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Losartan Potassium
Top 10

#6 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 Pheasant's Eye reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The Pheasant's Eye and Losartan Potassium records this page draws on were last updated July 10, 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 Pheasant's Eye

What is Pheasant's Eye?

  • Heart failure symptoms
  • Irregular or weak heartbeat
  • Fluid retention (as a diuretic)
  • Nervous heart complaints
  • Mild anxiety with heart palpitations

Pheasant's Eye (Adonis vernalis) is a toxic plant that contains heart-acting compounds similar to those in foxglove. It has been used in traditional and old European medicine for heart problems, but it is poisonous and has a very narrow margin of safety. You should not use it on your own — it should only ever be considered under direct medical supervision, if at all.

Adonis vernalis · Ranunculaceae · Dried above-ground parts (herb), including flowers, stems, and leaves · Tincture, dried herb extract, and standardized preparations (historically); rarely available as a non-prescription supplement

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

Pheasant's Eye: dosing

There is no safe, established over-the-counter dose for Pheasant's Eye, and we will not suggest one. Because the plant is toxic and the gap between an active dose and a poisonous dose is very small, dosing was historically left to trained practitioners using standardized, carefully measured preparations.We do not recommend using this plant on your own. If a product containing it is ever offered to you, do not take it without first speaking to a doctor or pharmacist. Always follow professional medical guidance rather than a product label alone.

From our Pheasant's Eye monograph — the full record covers uses, side effects and every documented interaction.

Read the full Pheasant's Eye monograph & all interactions
Medication

About Losartan

What Is Losartan Used For?

Brand name: Cozaar

Losartan tablets — available as branded Cozaar and several generic products — are used to treat high blood pressure (hypertension) in adults and children 6 years and older. Lowering blood pressure reduces the risk of strokes and heart attacks. Losartan tablets are also used to reduce the risk of stroke in people with high blood pressure who also have left ventricular hypertrophy (an enlarged left side of the heart). Note: evidence suggests this stroke-risk benefit may not apply to Black patients.

Losartan tablets are additionally approved to protect the kidneys in people with type 2 diabetes, high blood pressure, and signs of kidney damage (diabetic nephropathy). Arbli, the oral suspension form, shares these same approved uses.

Most-Reported Side Effects for Losartan Potassium

From FAERS, the FDA’s public side-effect reporting system (89,498 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Fatigue 6,464 reports
Nausea 5,301 reports
Diarrhea 5,184 reports
Dyspnea 4,689 reports
Dizziness 4,429 reports
See full Losartan drug information
Keep checking

Other Drugs & Pheasant's Eye

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

1Major
155Moderate
0Minor
2,673No known interaction
Major

1 interaction

Moderate

155 interactions

Showing 60 of 155 moderate interactions — see all 155 on the Pheasant's Eye page.

No interaction 2,673 drugs checked — show the list
Evidence & sources

Pheasant's Eye References

The 7 references that drive our Pheasant's Eye 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. Blumenthal M, ed. The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. Trans. S. Klein. Boston, MA: American Botanical Council, 1998.
  2. Newall CA, Anderson LA, Philpson JD. Herbal Medicine: A Guide for Healthcare Professionals. London, UK: The Pharmaceutical Press, 1996.
  3. Ellenhorn MJ, et al. Ellenhorn's Medical Toxicology: Diagnoses and Treatment of Human Poisoning. 2nd ed. Baltimore, MD: Williams & Wilkins, 1997.
  4. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.
  5. Burnham TH, ed. Drug Facts and Comparisons, Updated Monthly. Facts and Comparisons, St. Louis, MO.
  6. Robbers JE, Tyler VE. Tyler's Herbs of Choice: The Therapeutic Use of Phytomedicinals. New York, NY: The Haworth Herbal Press, 1999.
  7. Shang X, Miao X, Yang F, et al. The genus Adonis as an important cardiac folk medicine: A review of the ethnobotany, phytochemistry and pharmacology. Front Pharmacol. 2019;10:25. 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 Pheasant's Eye and Losartan Potassium Together: Common Questions

Is it safe to take Pheasant's Eye with Losartan Potassium?
We do not list a known interaction between Pheasant's Eye and Losartan Potassium. 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 Pheasant's Eye and Losartan Potassium have any of the same side effects?
Yes — our sources link each of them separately to 4 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 Pheasant's Eye and Losartan Potassium 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 Pheasant's Eye in each. That is a conversation for your prescriber, especially if Losartan Potassium is being adjusted to a target.
How was the Pheasant's Eye and Losartan Potassium combination checked?
Interactions in our licensed database are recorded against drug classes. Losartan Potassium is filed under 7 classifications, and Pheasant's Eye has documented interactions with 7 drug classes — none of Losartan Potassium'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 Pheasant's Eye interact with any other medications?
Yes. Pheasant's Eye has 156 documented drug interactions in our database — Losartan Potassium 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 Losartan Potassium interact with any supplements?
Yes. Losartan Potassium has documented interactions with 253 supplements in our database — Pheasant's Eye is not one of them. The Losartan Potassium 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 Losartan Potassium and Pheasant's Eye?

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.