Interactions on record — worth a quick check against your medications. Check your meds →
Dietary supplement

Olive Leaf Plus 500 mg Ingredients & Drug Interactions

by Highland Laboratories

Olive Leaf Plus 500 mg label
See full label image
Tablet Or Pill Category: Botanical
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Olive Leaf Plus 500 mg against your medications. The heart of this page is the interaction checker and the full interaction report — how this product’s ingredients may interact with prescription and over-the-counter medicines you may be taking.

Around that, we add a pharmacist’s high-level view of the product as a whole — what’s inside, the evidence for its stated use, how transparent the label is, and what safety data exists — so you can see the full picture in one place. It’s educational information from our licensed clinical databases and the clinical staff at HelloPharmacist — not medical advice — and we don’t sell or endorse products. Our editorial policy

The interaction bottom line Most serious interaction: Moderate

Olive Leaf Plus 500 mg is a dietary supplement by Highland Laboratories with 3 active ingredients. Its ingredients are commonly taken for heart health, high blood pressure, high cholesterol.Based on those ingredients, 817 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Echinacea angustifolia, Sambucus canadensis. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Olive Leaf Plus 500 mg by Highland Laboratories

Ask about any prescription or over-the-counter medication and we check it for interactions with Olive Leaf Plus 500 mg by Highland Laboratories — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of Olive Leaf Plus 500 mg by Highland Laboratories

Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Aug 27, 2026

What’s inside

Low disclosure
Ingredient Transparency · database check
Low

Most active ingredients don't disclose an individual amount — you can't tell how much of each you're getting.

Why this rating?
  • The label discloses an exact amount for 1 of its 3 active ingredients.

Olive Leaf Plus contains 3 active ingredients in each tablet. The main one is olive leaf standardized extract, a concentrated form of compounds from the olive plant.

It also includes echinacea angustifolia (also called narrow-leaved coneflower), an herbal immune supporter, and American elder (Sambucus canadensis), made from the berries and flowers of the elderberry plant. The tablet also contains inactive ingredients — cellulose, calcium phosphate, and vegetable stearate — which are fillers and binders that hold the tablet together.

Does it work?

Couldn't assess
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed
Not assessable

The label doesn't state a purpose we can grade — see each ingredient's own graded uses on its monograph instead.

Why this rating?
  • We looked at the product name, claims, and label statements and couldn't find a stated purpose to grade.

The evidence we hold for the active ingredients in this product doesn't establish that they work for any specific condition. Olive leaf extract has insufficient reliable evidence to rate for osteoporosis, indigestion, exercise-related respiratory infections, shingles, flu, and osteoarthritis.

Echinacea similarly has insufficient reliable evidence for anxiety, athletic performance, ADHD, burns, chronic fatigue syndrome, and migraines. American elder has insufficient reliable evidence for asthma, cancer, headache, common cold, cough, and gas.

If you're considering this product for a particular health goal, that's a conversation to have with your doctor or pharmacist.

The evidence, ingredient by ingredient Olive Echinacea American Elder

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 3 of the 3 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 3 of 3.
  • General safety write-ups exist for 3 of 3.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Olive leaf extract is generally well tolerated when used, though concentrated supplements are less studied than olive oil and olives as food. The most common side effects reported are headache and stomach discomfort; one person in a trial reported acne.

Echinacea is generally well tolerated short-term but may cause abdominal pain, constipation, diarrhea, heartburn, nausea, vomiting, or rashes. Rare serious effects include severe allergic reactions and hepatitis — people sensitive to ragweed and related plants (like chrysanthemums and daisies) are at higher risk for allergic reactions.

American elder's safety in medicinal amounts is not well studied, but reported side effects include dizziness, nausea, numbness, vomiting, and weakness; cooked ripe berries are safer than raw or unripe parts. Regarding pregnancy and lactation: echinacea is rated possibly safe in pregnancy but has insufficient data on breastfeeding; American elder is rated likely unsafe in both pregnancy and breastfeeding, so it should be avoided during these times; data on olive leaf extract during pregnancy and breastfeeding is not on file.

Side effects, ingredient by ingredient Olive Echinacea American Elder

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

The most serious documented interaction for these ingredients is Moderate. Check your medications for a personalized result.

Why this rating?
  • 2 of the 3 matched ingredients can interact with medications — American Elder, Echinacea.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; lithium.
  • For scale: 818 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Check with your doctor or pharmacist before taking this product if you're on any of these: immunosuppressants (echinacea may interfere with how well they work), drugs metabolized by CYP1A2 enzymes or caffeine-containing products (echinacea may raise their levels), CYP3A4 substrates — a broad class including some cholesterol drugs, some blood pressure medications, and others (echinacea and American elder may affect their levels unpredictably), lithium (American elder may raise its levels), blood thinners like warfarin, sedatives like midazolam, etoposide or other cancer drugs, or HIV medications like lopinavir/ritonavir. If you take any of these, talk it over with your healthcare provider first.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFormula with limited ingredient disclosure with no assessable stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

This product may appeal to someone looking for herbal support, but because the effectiveness evidence for all three ingredients is insufficient, it's unclear whether it will deliver on any claimed benefits. The bigger concern is the medication interactions — particularly if you take immunosuppressants, blood thinners, lithium, sedatives, or cancer drugs like etoposide.

Women who are pregnant or breastfeeding should avoid American elder. Before you start, check your exact medications with your doctor or pharmacist.

Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI

Assessment coverage: 3 of 3 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Oct 21, 2017.

This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed

At a glance

General information

Key facts about Olive Leaf Plus 500 mg, straight from the product label.

Brand Highland Laboratories
Barcode (UPC) 768305121560
Net contents 60 Vegetarian Tablet(s)
Market status On market
Date entered into DSLD Oct 21, 2017
DSLD ID 79744
Product type Botanical
Supplement form Tablet Or Pill
Dietary claims / uses All Other
Intended target group(s) Adult (18 - 50 Years), Gluten Free, Dairy Free, Sugar Free
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for Olive Leaf Plus 500 mg by Highland Laboratories, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
1 Vegetarian Tablet(s)
Maximum serving Sizes:
1 Vegetarian Tablet(s)
UPC/BARCODE
768305121560
IngredientAmount% DV
Olive leaf standardized extract500 mg--
Echinacea angustifolia0 NP--
Sambucus canadensis0 NP--

Other ingredients: Cellulose, Calcium Phosphate, Vegetable Stearate

Tap any ingredient to jump to its full detail below.

Label statements
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
General Statements

Standardized botanical

% Daily Value

This product complies with USP standards for dietary supplements.

FDA Statement of Identity

An Herbal Supplement

Seals/Symbols

GMP Quality Assured Earth Friendly

Formulation

No corn, soy, salt, yeast, gluten, milk & egg products, sugar, starch, or preservatives.

Suggested/Recommended/Usage/Directions

One tablet daily, as a dietary supplement.

Brand IP Statement(s)

Formulated using the Sol-U-Tab system for rapid disintegration.

General

PR 1215

Is this label outdated? Report a formula or label change and our pharmacy team will review it.

See for yourself

Olive Leaf Plus 500 mg by Highland Laboratories label

The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.

Olive Leaf Plus 500 mg label

Label images are published by the NIH Dietary Supplement Label Database for the version of this product on file. Always read your actual product label.

View the full label (PDF)
What’s inside

The Ingredients in Olive Leaf Plus 500 mg by Highland Laboratories

These are the 3 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 Vegetarian Tablet(s) Dosage formTablet Or Pill Amounts shown are per serving.

Most supplement products combine several ingredients, and a medication can interact with the product through any one of them. Each ingredient below shows whether it has known drug interactions.

Olive leaf standardized extract

No known
interactions
500 mg per serving Form: Oleuropein

Olive comes from the same tree that gives us olives and olive oil, and its leaf and fruit contain antioxidant compounds like oleuropein and hydroxytyr...

Olive leaf standardized extract monograph & interactions

Echinacea angustifolia

Interacts with
816 drugs
0 NP per serving

Echinacea is a popular herb taken to help prevent or shorten the common cold, but study results are mixed and the overall benefit appears small at bes...

Echinacea angustifolia monograph & interactions

Sambucus canadensis

Interacts with
644 drugs
0 NP per serving

American elder is a North American plant whose cooked, ripe berries and flowers are used mainly for colds, flu, and general immune support. The scienc...

Sambucus canadensis monograph & interactions

Other (inactive) ingredients: Cellulose, Calcium Phosphate, Vegetable Stearate. These complete the product’s ingredient list but are not active constituents.

Interaction report

Olive Leaf Plus 500 mg by Highland Laboratories Drug Interactions

Want to check YOUR meds against Olive Leaf Plus 500 mg?

Ask about interactions with your drugs in plain English — “Can I take it with lisinopril?” — and we find you the answer in seconds, ingredient by ingredient.

 Go to the checker
817Drugs
816 Moderate 1 Minor

Ingredients driving the most interactions

Echinacea angustifolia 816
Sambucus canadensis 644

Individual Drug Interactions

The ingredients in Olive Leaf Plus 500 mg interact with 817 drugs. Click any drug to see the details.

2 of the 3 ingredients in Olive Leaf Plus 500 mg interact with drugs. Each result below shows which ingredient is responsible. Echinacea angustifolia Sambucus canadensis

Each ingredient & the kinds of drugs it affects

For each ingredient in Olive Leaf Plus 500 mg with known interactions, here are the types of medications they can affect. Open any type for the detail — or search your exact drug in the checker above.

Echinacea angustifolia12 drug types · 816 drugs

Caffeine

Echinacea can increase plasma levels of caffeine by inhibiting its metabolism.
Echinacea seems to increase plasma concentrations of caffeine by around 30%. This is likely due to inhibition of cytochrome P450 1A2 (CYP1A2) by echinacea.

Likelihood Probable Evidence B
Cytochrome P450 1A2 (Cyp1A2) Substrates

Echinacea might inhibit the metabolism of CYP1A2 and increase plasma levels of some drugs.
Echinacea appears to inhibit CYP1A2 enzymes in humans. Additionally, echinacea seems to increase plasma concentrations of caffeine, a CYP1A2 substrate, by around 30%. Theoretically, echinacea might increase levels of other drugs metabolized by CYP1A2.

Likelihood Possible Evidence B
Cytochrome P450 3A4 (Cyp3A4) Substrates

Echinacea may induce hepatic CYP3A4 and inhibit intestinal CYP3A4. This may increase or decrease levels of drugs metabolized by CYP3A4.
Several clinical trials have shown that taking echinacea for up to one month does not significantly affect the metabolism of various CYP3A4 substrates, including midazolam, docetaxel, etravirine, lopinavir-ritonavir, and darunavir-ritonavir. However, other clinical research shows that echinacea may increase the clearance of midazolam, suggesting that echinacea might induce CYP3A4. The discrepancy is thought to be due to differing effects of echinacea on intestinal versus hepatic CYP3A4 enzymes. Echinacea appears to induce hepatic CYP3A4 but inhibit intestinal CYP3A4. In some cases, these effects might cancel each other out, but in others, drug levels may be increased or decreased depending on the level of effect at hepatic and intestinal sites. The effect of echinacea on CYP3A4 activity may differ depending on the CYP3A4 substrate.

Likelihood Possible Evidence B
Etoposide (Vepesid)

Echinacea may increase levels of etoposide.
In one report, concomitant use of etoposide and echinacea was associated with more severe thrombocytopenia than the use of etoposide alone, suggesting inhibition of etoposide metabolism. Etoposide is a cytochrome P450 3A4 (CYP3A4) substrate. Echinacea has variable effects on CYP3A4, but some studies have reported inhibition of the enzyme.

Likelihood Possible Evidence D
Immunosuppressants

Echinacea has immunostimulant activity which may interfere with immunosuppressant therapy.
Theoretically, echinacea may interfere with immunosuppressant therapy because of its immunostimulant activity.

Likelihood Possible Evidence B
Darunavir (Prezista)

Theoretically, echinacea may interfere with the metabolism of darunavir; however, a small clinical study found no effect.
Darunavir is metabolized by cytochrome P450 3A4 (CYP3A4) and is administered with the CYP3A4 inhibitor ritonavir to increase its plasma concentrations. Echinacea has variable effects on CYP3A4, but administration of an E. purpurea root extract (Arkocapsulas Echinacea, Arkopharma) 500 mg four times daily for 14 days did not affect darunavir/ritonavir pharmacokinetics in 15 HIV-infected patients.

Likelihood Unlikely Evidence B
Dayquil Severe

Echinacea is reported to have varying effects on a number of Cytochrome P450 metabolizing enzymes in the liver, including CYP1A2 and CYP3A4, which play a role in acetaminophen and dextromethorphan metabolism (both contained in DayQuil Severe), respectively. Studies have reported both enzyme inhibition and induction, making it difficult to predict clinically significant drug interactions with reliability. Specific drug interaction studies reporting definitive results are rare, and potential drug interactions involving echinacea should likely be taken on a case-by-case basis. Based on what we know about how acetaminophen and dextromethorphan are metabolized, the risk of a clinically significant interaction between echinacea and DayQuil Severe is low.

Likelihood Unlikely Evidence A
Docetaxel (Taxotere)

Theoretically, echinacea may interfere with the metabolism of docetaxel; however, a small clinical study found no effect.
Docetaxel is metabolized by cytochrome P450 3A4 (CYP3A4). Echinacea has variable effects on CYP3A4, but taking E. purpurea whole plant extract (Echinaforce, A. Vogel Biopharma AG) 20 drops three times daily for 2 weeks did not alter the pharmacokinetics of docetaxel in one clinical study.

Likelihood Unlikely Evidence B
Etravirine (Intelence)

Theoretically, echinacea may interfere with the metabolism of etravirine; however, a small clinical study found no effect.
Etravirine is metabolized by cytochrome P450 3A4 (CYP3A4). Echinacea has variable effects on CYP3A4, but taking E. purpurea root extract (Arkocapsulas Echinacea, Arkopharma) 500 mg three times daily for 14 days did not alter the pharmacokinetics of etravirine in HIV-infected patients.

Likelihood Unlikely Evidence B
Lopinavir/Ritonavir (Kaletra)

Theoretically, echinacea may interfere with the metabolism of lopinavir; however, a small clinical study found no effect.
Lopinavir is metabolized by cytochrome P450 3A4 (CYP3A4) and is administered with the CYP3A4 inhibitor ritonavir to increase its plasma concentrations. Echinacea has variable effects on CYP3A4, but taking E. purpurea (Echinamide, Natural Factors Nutritional Products, Inc.) 500 mg three times daily for 14 days did not alter the pharmacokinetics of lopinavir/ritonavir in healthy volunteers.

Likelihood Unlikely Evidence B
Midazolam (Versed)

Theoretically, echinacea may increase the metabolism of intravenous midazolam.
Echinacea induces hepatic CYP3A4 and might decrease plasma levels of midazolam by about 20%, reducing the effectiveness of intravenous midazolam. Echinacea also appears to inhibit intestinal CYP3A4, which could theoretically increase the bioavailability of oral midazolam. This may cancel out the decrease in availability caused by induction of hepatic CYP3A4, such that overall plasma levels after oral administration of midazolam are not affected by echinacea.

Likelihood Possible Evidence B
Warfarin (Coumadin)

Echinacea seems to increase the clearance of warfarin, although the effect may not be clinically significant.
Preliminary clinical research in healthy male volunteers suggests that taking echinacea increases the clearance of the active S-isomer of warfarin after a single dose of warfarin, but there was not a clinically significant effect on the INR.

Likelihood Possible Evidence B
Echinacea angustifolia full monograph & interactions

Sambucus canadensis2 drug types · 644 drugs

Cytochrome P450 3A4 (Cyp3A4) Substrates

Theoretically, taking American elder might increase levels of CYP3A4 substrates.
In vitro research shows that American elder inhibits CYP3A4 enzymes.

Likelihood Possible Evidence D
Lithium

Theoretically, American elder might reduce excretion and increase levels of lithium.
American elder is thought to have diuretic properties. Theoretically, American elder might reduce the excretion of lithium, increasing serum levels.

Likelihood Probable Evidence D
Sambucus canadensis full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Olive Leaf Plus 500 mg, from the product label.

Highland Laboratories

See all Highland Laboratories products
Name
Highland Laboratories
Pharmacist Counseling Corner

Olive Leaf Plus 500 mg by Highland Laboratories: Common Questions

Does Olive Leaf Plus 500 mg by Highland Laboratories interact with any medications?
Yes. Based on its ingredients, Olive Leaf Plus 500 mg has a known interaction with 817 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Olive Leaf Plus 500 mg contains 3 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Is it safe to take Olive Leaf Plus if I'm pregnant?
Echinacea is rated possibly safe in pregnancy, but data on olive leaf extract and American elder during pregnancy is limited — American elder is actually rated likely unsafe. Because the safety picture isn't clear, talk with your doctor or pharmacist before taking this product if you're pregnant; they can help you decide whether it's right for you.
Can I take this while breastfeeding?
American elder is rated likely unsafe while breastfeeding and should be avoided. Data on whether echinacea and olive leaf extract are safe during breastfeeding isn't on file. If you're breastfeeding, talk with your doctor or pharmacist before starting this product.
What side effects might I experience?
The most common side effects are headache and stomach discomfort from the olive leaf, and abdominal pain, constipation, diarrhea, heartburn, nausea, vomiting, or rashes from the echinacea. American elder may cause dizziness, nausea, numbness, or weakness. Rare but serious allergic reactions have been reported with echinacea, especially in people sensitive to ragweed and related plants.
Does this product actually work for anything?
The evidence we hold doesn't establish that any of the three ingredients work for specific conditions — all have insufficient reliable evidence for the uses they're typically marketed for. If you're considering it for a particular reason, ask your doctor whether there's better-studied support out there.
What's the difference between Olive Leaf Plus and just eating olives or olive oil?
Olive oil and olives as food are very safe and well tolerated. Olive Leaf Plus is a concentrated supplement, which is less studied and carries more unknown risks — that's why the caution is stronger for the concentrated form. The same goes for echinacea and American elder in supplement form versus whole foods.
Will this interact with my medications?
This product does have documented interactions with many medications — most seriously with immunosuppressants, certain cancer drugs, lithium, and blood thinners. Use the medication checker on this page with your exact prescriptions, or talk with your pharmacist or doctor before starting.

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

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Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

Olive Leaf Plus 500 mg label
Go deeper

The Full Monographs Behind Olive Leaf Plus 500 mg’s Ingredients

Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.

Herb & supplement monograph

Olive

Olive comes from the same tree that gives us olives and olive oil, and its leaf and fruit contain antioxidant compounds like oleuropein and hydroxytyrosol. Olive oil as part of a Mediterrane...

Read the full Olive monograph → Herb & supplement monograph

Echinacea

Interacts with 816 drugs

Echinacea is a popular herb taken to help prevent or shorten the common cold, but study results are mixed and the overall benefit appears small at best. It is generally well tolerated for sh...

Read the full Echinacea monograph → Herb & supplement monograph

American Elder

Interacts with 644 drugs

American elder is a North American plant whose cooked, ripe berries and flowers are used mainly for colds, flu, and general immune support. The science behind these uses is limited and most...

Read the full American Elder monograph →
Sources

Sources & How We Checked

Olive Leaf Plus 500 mg's label data comes from the NIH Dietary Supplement Label Database; the ingredient interaction data is from the Natural Medicines database, reviewed by our pharmacists.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

The 55 references behind this product’s interaction data

Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.

Olive 2 references
  1. Liccardi G, D'Amato M, D'Amato G. Oleaceae pollinosis: a review. Int Arch Allergy Immunol 1996;111:210-7. PubMed
  2. Somerville V, Moore R, Braakhuis A. The effect of olive leaf extract on upper respiratory illness in high school athletes: A randomised control trial. Nutrients. 2019;11(2). pii: E358. PubMed

See these in context on the Olive monograph →

Echinacea 51 references
  1. Mullins RJ. Echinacea-associated anaphylaxis. Med J Aust 1998;168:170-1. PubMed
  2. Mullins RJ. Allergic reactions to Echinacea. J Allergy Clin Immunol 2000;104:S340-341 (Abstract 1003).
  3. Chavez ML, Chavez PI. Echinacea. Hosp Pharm 1998;33:180-8.
  4. Grimm W, Muller HH. A randomized controlled trial of the effect of fluid extract of Echinacea purpurea on the incidence and severity of colds and respiratory infections. Am J Med 1999;106:138-43. PubMed
  5. Taylor JA, Weber W, Standish L, et al. Efficacy and safety of echinacea in treating upper respiratory tract infections in children: a randomized controlled trial. JAMA 2003;290:2824-30.. PubMed
  6. Luettig B, Steinmuller C, Gifford GE, et al. Macrophage activation by the polysaccharide arabinogalactan isolated from plant cell cultures of Echinacea purpurea. J Natl Cancer Inst 1989;81:669-75. PubMed
  7. Stimpel M, Proksch A, Wagner H, et al. Macrophage activation and induction of macrophage cytotoxicity by purified polysaccharide fractions from the plant Echinacea purpurea. Infect Immun 1984;46:845-9. PubMed
  8. Budzinski JW, Foster BC, Vandenhoek S, Arnason JT. An in vitro evaluation of human cytochrome P450 3A4 inhibition by selected commercial herbal extracts and tinctures. Phytomedicine 2000;7:273-82. PubMed
  9. Gallo M, Sarkar M, Au W, et al. Pregnancy outcome following gestational exposure to echinacea: A prospective controlled study. Arch Intern Med 2000;160:3141-3. PubMed
  10. Soon SL, Crawford RI. Recurrent erythema nodosum associated with echinacea herbal therapy. J Am Acad Dermatol 2001;44:298-9. PubMed
  11. Mullins RJ, Heddle R. Adverse reactions associated with echinacea: the Australian experience. Ann Allergy Asthma Immunol 2002;88:42-51. PubMed
  12. Logan JL, Ahmed J. Critical hypokalemic renal tubular acidosis due to Sjogren's syndrome: association with the purported immune stimulant echinacea. Clin Rheumatol 2003;22:158-9.
  13. Schulten B, Bulitta M, Ballering-Bruhl B, et al. Efficacy of Echinacea purpurea in patients with a common cold. A placebo-controlled, randomised, double-blind clinical trial. Arzneimittelforschung 2001;51:563-8.. PubMed
  14. Yale SH, Glurich I. Analysis of the inhibitory potential of Ginkgo biloba, Echinacea purpurea, and Serenoa repens on the metabolic activity of cytochrome P450 3A4, 2D6, and 2C9. J Altern Complement Med 2005;11:433-9.
  15. Yale SH, Liu K. Echinacea purpurea therapy for the treatment of the common cold: a randomized, double-blind, placebo-controlled clinical trial. Arch Intern Med 2004;164:1237-41. PubMed
  16. Gorski JC, Huang S, Zaheer NA, et al. The effect of echinacea (Echinacea purpurea root) on cytochrome P450 activity in vivo.Clin Pharmacol Ther 2003;73 (Abstract PDII-A-8):P94. PubMed
  17. Lee AN, Werth VP. Activation of autoimmunity following use of immunostimulatory herbal supplements. Arch Dermatol 2004;140:723-7. PubMed
  18. Goel V, Lovlin R, Barton R, et al. Efficacy of a standardized echinacea preparation (Echinilin) for the treatment of the common cold: a randomized, double-blind, placebo-controlled trial. J Clin Pharm Ther 2004;29:75-83.
  19. Barrett B. Medicinal properties of Echinacea: a critical review. Phytomedicine 2003;10:66-86. PubMed
  20. Huntley AL, Thompson Coon J, Ernst E. The safety of herbal medicinal products derived from Echinacea species: a systematic review. Drug Saf 2005;28:387-400. PubMed
  21. Turner RB, Bauer R, Woelkart K, et al. An evaluation of Echinacea angustifolia in experimental rhinovirus infections. N Engl J Med 2005;353:341-8.
  22. Gurley BJ, Gardner SF, Hubbard MA, et al. In vivo assessment of botanical supplementation on human cytochrome P450 phenotypes: Citrus aurantium, Echinacea purpurea, milk thistle, and saw palmetto. Clin Pharmacol Ther 2004;76:428-40. .
  23. Perri D, Dugoua JJ, Mills E, Koren G. Safety and efficacy of echinacea (Echinacea augustafolia, e. purpurea and e. pallida) during pregnancy and lactation. Can J Clin Pharmacol 2006;13:e262-7.
  24. Kocaman O, Hulagu S, Senturk O. Echinacea-induced severe acute hepatitis with features of cholestatic autoimmune hepatitis. Eur J Intern Med 2008;19:148. PubMed
  25. Barrett B, Brown R, Rakel D. et al. Echinacea for treating the common cold: a randomized trial. Ann Intern Med 2010;153:769-77. PubMed
  26. Press Release: Echinacea herbal products should not be used in children under 12 years old. Medicines and Healthcare Products Regulatory Agency (UK). August 20, 2012. Available at: www.mhra.gov.uk/NewsCentre/Pressreleases/CON180627. (Accessed 21 October
  27. Barrett B, Brown R, Rakel D, Rabago D, et al. Placebo effects and the common cold: a randomized controlled trial. Ann.Fam.Med 2011;9:312-22. PubMed
  28. Haller J, Freund, TF, Pelczer, KG, et al. The anxiolytic potential and psychotropic side effects of an echinacea preparation in laboratory animals and healthy volunteers. Phytother.Res. 2013;27:54-61.
  29. Grbic J, Wexler I, Celenti R, et al. A phase II trial of a transmucosal herbal patch for the treatment of gingivitis. J Am Dent.Assoc. 2011;142:1168-75. PubMed
  30. Schapowal A, Berger D, Klein P, et al. Echinacea/sage or chlorhexidine/lidocaine for treating acute sore throats: a randomized double-blind trial. Eur.J Med Res 9-1-2009;14:406-12. PubMed
  31. Bossaer JB and Odle BL. Probable etoposide interaction with Echinacea. J.Diet.Suppl 2012;9:90-5.
  32. Abdul MI, Jiang X, Williams KM, et al. Pharmacokinetic and pharmacodynamic interactions of echinacea and policosanol with warfarin in healthy subjects. Br J Clin.Pharmacol. 2010;69:508-15. PubMed
  33. Kemp, D. E. and Franco, K. N. Possible leukopenia associated with long-term use of echinacea. J Am Board Fam.Pract. 2002;15(5):417-419.
  34. Liatsos, G., Elefsiniotis, I., Todorova, R., and Moulakakis, A. Severe thrombotic thrombocytopenic purpura (TTP) induced or exacerbated by the immunostimulatory herb Echinacea. Am J Hematol. 2006;81(3):224.
  35. Penzak, S. R., Robertson, S. M., Hunt, J. D., Chairez, C., Malati, C. Y., Alfaro, R. M., Stevenson, J. M., and Kovacs, J. A. Echinacea purpurea significantly induces cytochrome P450 3A activity but does not alter lopinavir-ritonavir exposure in healthy s
  36. Maskatia, Z. K. and Baker, K. Hypereosinophilia associated with echinacea use. South.Med J 2010;103(11):1173-1174. PubMed
  37. Parnham MJ. Benefit-risk assessment of the squeezed sap of the purple coneflower (Echinacea purpurea) for long-term oral immunostimulation. Phytomed 1996;3:95-102. PubMed
  38. Schroder-Aasen T, Molden G, Nilsen OG. In vitro inhibition of CYP3A4 by the multiherbal commercial product Sambucus Force and its main constituents Echinacea purpurea and Sambucus nigra. Phytother Res 2012;26(11):1606-13.
  39. Moltó J, Valle M, Miranda C, et al. Herb-drug interaction between Echinacea purpurea and darunavir-ritonavir in HIV-infected patients. Antimicrob Agents Chemother 2011;55(1):326-30.
  40. Goey AK, Meijerman I, Rosing H, et al. The effect of Echinacea purpurea on the pharmacokinetics of docetaxel. Br J Clin Pharmacol 2013;76(3):467-74.
  41. Moltó J, Valle M, Miranda C, et al. Herb-drug interaction between Echinacea purpurea and etravirine in HIV-infected patients. Antimicrob Agents Chemother 2012;56(10):5328-31. PubMed
  42. Lawrenson JA, Walls T, Day AS. Echinacea-induced acute liver failure in a child. J Paediatr Child Health 2014;50(10):841.
  43. Hansen TS, Nilsen OG. In vitro CYP3A4 metabolism: inhibition by Echinacea purpurea and choice of substrate for the evaluation of herbal inhibition. Basic Clin Pharmacol Toxicol 2008;103:445-9.
  44. Gabranis I, Koufakis T1, Papakrivos I, Batala S. Echinacea-associated acute cholestatic hepatitis. J Postgrad Med. 2015;61(3):211-2. PubMed
  45. Jalloh MA, Gregory PJ, Hein D, et al. Dietary supplement interactions with antiretrovirals: a systematic review. Int J STD AIDS. 2017 Jan;28(1):4-15. PubMed
  46. Karsch-Völk M, Barrett B, Kiefer D, Bauer R, Ardjomand-Woelkart K, Linde K. Echinacea for preventing and treating the common cold. Cochrane Database Syst Rev.2014;(2):CD000530. doi: 10.1002/14651858.CD000530.pub3. PubMed
  47. Hoban CL, Byard RW, Musgrave IF. Analysis of spontaneous adverse drug reactions to echinacea, valerian, black cohosh and ginkgo in Australia from 2000 to 2015. J Integr Med. 2019;17(5):338-343. PubMed
  48. Ogal M, Johnston SL, Klein P, Schoop R. Echinacea reduces antibiotic usage in children through respiratory tract infection prevention: a randomized, blinded, controlled clinical trial. Eur J Med Res. 2021 Apr 8;26(1):33. PubMed
  49. Lopresti AL, Smith SJ. An investigation into the anxiety-relieving and mood-enhancing effects of Echinacea angustifolia (EP107 ™): A randomised, double-blind, placebo-controlled study. J Affect Disord 2021;293:229-237.
  50. Weishaupt R, Buchkov A, Kolev E, Klein P, Schoop R. Reduction of viral load in patients with acute sore throats: Results from an observational clinical trial with Echinacea / Salvia lozenges [published online ahead of print, 2023 Mar 8]. Complement Med Re
  51. Sumer J, Keckeis K, Scanferla G, et al. Novel Echinacea formulations for the treatment of acute respiratory tract infections in adults-A randomized blinded controlled trial. Front Med (Lausanne) 2023;10:948787. PubMed

See these in context on the Echinacea monograph →

American Elder 2 references
  1. The Review of Natural Products by Facts and Comparisons. St. Louis, MO: Wolters Kluwer Co., 1999.
  2. Budzinski JW, Foster BC, Vandenhoek S, Arnason JT. An in vitro evaluation of human cytochrome P450 3A4 inhibition by selected commercial herbal extracts and tinctures. Phytomedicine 2000;7:273-82. PubMed

See these in context on the American Elder monograph →

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

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