Major interaction on record — check this product against your medications before combining. Based on 2 of 3 ingredients. Check your meds →
Dietary supplement

Echinacea Ingredients & Drug Interactions

by Solgar

Echinacea label
See full label image
Capsule Category: Botanical With Nutrients
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 23, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Echinacea 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: Major

Echinacea is a dietary supplement by Solgar with 3 active ingredients. Its ingredients are commonly taken for common cold, flu and respiratory infections, immune support.Based on those ingredients, 991 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Echinacea extract, Vitamin A. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Echinacea by Solgar

Ask about any prescription or over-the-counter medication and we check it for interactions with Echinacea by Solgar — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of Echinacea by Solgar

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 Jul 23, 2026

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 3 of its 3 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

This product contains three active ingredients: echinacea extract, vitamin A, and raw echinacea powder. The echinacea—provided both as an extract and as the whole dried plant powder—is included for its potential immune-supporting properties, though evidence for specific uses is limited.

Vitamin A is added as a nutrient, and the product also contains three inactive ingredients (vegetable cellulose, vegetable magnesium stearate, and water) that serve as the capsule material and binding agents.

Does it work?

Not established
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 established

The graded evidence we hold for these ingredients covers different conditions than the ones this product is marketed for, so there's no established rating for its stated use.

Why this rating?
  • The label markets this product for: immune support and common cold.
  • We looked for evidence on: Influenza, Upper respiratory tract infection (URTI), Respiratory infection, Throat infection.
  • The closest evidence on file: Vitamin A is rated "Insufficient Reliable Evidence To Rate" for Upper respiratory tract infection (URTI) (Natural Medicines).
  • Also on file: Echinacea is rated "Insufficient Reliable Evidence To Rate" for Upper respiratory tract infection (URTI), Influenza.

The data we hold doesn't establish effectiveness for echinacea for anxiety, athletic performance, ADHD, burns, chronic fatigue syndrome, or migraine headache—the evidence is simply insufficient. Vitamin A, on the other hand, is rated effective for vitamin A deficiency and possibly effective for oral leukoplakia, aging skin, measles, ulcerative colitis, and bronchopulmonary dysplasia.

If you're considering this product for a specific condition, it's worth asking your doctor or pharmacist whether the ingredients are backed by evidence for your particular use.

The evidence, ingredient by ingredient Echinacea Vitamin A

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 2 of the 2 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 2 of 2.
  • General safety write-ups exist for 2 of 2.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Echinacea is generally well tolerated over the short term, but it can cause allergic reactions—particularly if you're sensitive to ragweed or related plants like chrysanthemums, marigolds, or daisies. Most common side effects include stomach upset, nausea, diarrhea, constipation, heartburn, abdominal pain, and rashes.

Rarely, severe allergic reactions and liver damage have been reported. Vitamin A is safe at recommended amounts, but high doses build up in your body and can cause serious toxicity, including liver damage, headache, and dry or peeling skin.

The safety notes advise caution with echinacea—it's best to avoid it unless your doctor approves, as evidence is limited. For vitamin A, high-dose supplements should be avoided unless directed by a clinician; stick to normal dietary and recommended supplement amounts.

Side effects, ingredient by ingredient Echinacea Vitamin A

Meds to double-check

Major interaction found
Known Interaction Concern · database check
Major identified

At least one ingredient has a documented Major-severity interaction. Check your medications for a personalized result.

Why this rating?
  • 2 of the 2 matched ingredients can interact with medications — Vitamin A, Echinacea.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs.
  • For scale: 992 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.

Before you start this, double-check with your doctor or pharmacist if you take retinoids (vitamin A derivatives used for acne or skin conditions)—that's a Major severity risk. Also flag any medications broken down by your liver (CYP1A2 or CYP3A4 substrates, including certain sedatives, HIV drugs, and chemotherapy agents), blood thinners like warfarin, immunosuppressants, any drugs that can damage the liver, tetracycline antibiotics, or anything with caffeine.

Echinacea may change how your body handles these.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with no established evidence rating for its marketed use. Major medication interactions have been identified, and safety information is well characterized.

If you take any medications—especially blood thinners, sedatives, HIV drugs, chemotherapy, immunosuppressants, or anything processed through your liver—you need to check this product against your own medications before starting it. If you're sensitive to ragweed or its plant cousins, be cautious.

Talk with your own doctor or pharmacist about whether this product makes sense for your situation and to clear it with any medications you're on.

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 Mar 24, 2020.

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 Echinacea, straight from the product label.

Brand Solgar
Barcode (UPC) 033984038714
Net contents 250 Vegetable Capsule(s)
Market status On market
Date entered into DSLD Mar 24, 2020
DSLD ID 216256
Product type Botanical With Nutrients
Supplement form Capsule
Dietary claims / uses All Other
Intended target group(s) Vegetarian, Adult (18 - 50 Years), Kosher, 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 Echinacea by Solgar, 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 Capsule(s)
Maximum serving Sizes:
3 Capsule(s)
UPC/BARCODE
033984038714
IngredientAmount% DV
Echinacea extract65 mg--
Vitamin A135 IU3%
raw Echinacea powder265 mg--

Other ingredients: Vegetable Cellulose, Vegetable Magnesium Stearate, Water

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.
Formulation

Solgar's Full Potency Herbs include traditional herbal extracts in a base of active raw herbs to ensure that the full benefits are derived from the herbs. These products combine the advantages of both raw herbs and their active principles in the form of dry extracts. Our herbal formulas are specially prepared to include all the naturally occurring, synergistic constituents of the herb and not just selected, isolated active phytochemicals. Solgar's herbal products offer the highest quality, purest herbs available worldwide.

Suitable for vegetarians

Full potency herbs

This product is free of sugar, salt, corn, yeast, wheat, soy and dairy products and is formulated without the use of preservatives, flavors or colors of any kind.

Formula

Solgar's KOF-K certification #K-1250

(Echinacea purpurea)

General Statements

Solgar since 1947

FDA Statement of Identity

Dietary Supplement

Seals/Symbols

K Parve (Kosher)

Precautions

May contain vegetable glycerin.

If you are pregnant, nursing, taking any medication or have a medical condition, please consult your healthcare practitioner before taking any dietary supplement.

Keep out of reach of children.

Do not use if outer bottle seal is missing, torn or damaged in any way.

Suggested/Recommended/Usage/Directions

Suggested Use: As a dietary supplement for adults, one (1) to three (3) vegetable capsules daily, preferably at mealtimes, or as directed by a healthcare practitioner.

Storage

To assure freshness and potency, store at room temperature 15 degrees-30 degrees C (59 degrees-86 degrees F). Store away from heat, light and moisture.

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

See for yourself

Echinacea by Solgar label

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

Echinacea 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 Echinacea by Solgar

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

Serving size1 Capsule(s) Dosage formCapsule 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.

Echinacea extract

Interacts with
816 drugs
65 mg 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 extract monograph & interactions

Vitamin A

Interacts with
387 drugs
135 IU per serving

Vitamin A is an essential nutrient important for vision, skin, immune function, and growth. Most people get enough from a balanced diet, and supplemen...

Vitamin A monograph & interactions

Raw Echinacea powder

Interacts with
816 drugs
265 mg 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...

Raw Echinacea powder monograph & interactions

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

Interaction report

Echinacea by Solgar Drug Interactions

Want to check YOUR meds against Echinacea?

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
991Drugs
9 Major 981 Moderate 1 Minor

Ingredients driving the most interactions

Echinacea extract 816
Vitamin A 387

Individual Drug Interactions

The ingredients in Echinacea interact with 991 drugs. Click any drug to see the details.

2 of the 3 ingredients in Echinacea interact with drugs. Each result below shows which ingredient is responsible. Echinacea extract Vitamin A

Each ingredient & the kinds of drugs it affects

For each ingredient in Echinacea 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 extract12 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 extract full monograph & interactions

Vitamin A4 drug types · 387 drugs

Retinoids

Concomitant use of retinoids with vitamin A supplements might produce supratherapeutic vitamin A levels.
Retinoids, which are vitamin A derivatives, could have additive toxic effects when taken with vitamin A supplements.

Likelihood Probable Evidence D
Hepatotoxic Drugs

Theoretically, taking high doses of vitamin A in combination with other potentially hepatotoxic drugs might increase the risk of liver disease.
The tolerable upper intake level (UL) is the highest level of intake that is likely to pose no risk of adverse effects. Doses of vitamin A above the UL can cause hepatotoxicity, ranging from elevated liver enzymes to liver failure.

Likelihood Possible Evidence C
Tetracycline Antibiotics

Theoretically, taking tetracycline antibiotics with high doses of vitamin A can increase the risk of pseudotumor cerebri.
Benign intracranial hypertension (pseudotumor cerebri) can occur with tetracyclines and with acute or chronic vitamin A toxicity. Case reports suggest that taking tetracyclines and vitamin A concurrently can increase the risk of this condition. Avoid high doses of vitamin A in people taking tetracyclines chronically.

Likelihood Possible Evidence D
Warfarin (Coumadin)

Theoretically, high doses of vitamin A could increase the risk of bleeding with warfarin.
Vitamin A toxicity is associated with hemorrhage and hypoprothrombinemia, possibly due to vitamin K antagonism. Advise patients taking warfarin to avoid doses of vitamin A above the tolerable upper intake level of 10,000 IU/day for adults.

Likelihood Possible Evidence D
Vitamin A full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Echinacea, from the product label.

Solgar

See all Solgar products
Name
Solgar Vitamin and Herb
City
Leonia
State
N.J.
ZipCode
07605
Phone Number
1-877-765-4274
Web Address
www.solgar.com
Pharmacist Counseling Corner

Echinacea by Solgar: Common Questions

Does Echinacea by Solgar interact with any medications?
Yes. Based on its ingredients, Echinacea has a known interaction with 991 medications, including 9 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Echinacea 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 this while pregnant or breastfeeding?
For echinacea, the data rates it as possibly safe in pregnancy, but there isn't enough information about breastfeeding. For vitamin A, the facts show it's likely safe during lactation but possibly unsafe during pregnancy—particularly at high doses—because of birth defect risk. You should talk with your own doctor or pharmacist for personalized advice before taking this product if you're pregnant or nursing.
Will this help with colds or the flu?
We don't have effectiveness data in our facts for echinacea and colds or flu. The uses we do have ratings for—anxiety, athletic performance, ADHD, burns, chronic fatigue, and migraines—all show insufficient evidence. If you're thinking about it for immune support or illness prevention, ask your doctor or pharmacist whether echinacea is backed by evidence for what you need.
Can this cause liver damage?
Liver damage from echinacea is rare, but cases of hepatitis have been reported. Vitamin A, especially at high doses, can also damage the liver. If you have liver disease or take other drugs that can damage the liver, talk with your doctor or pharmacist before starting this product.
What are the most common side effects?
With echinacea, the most common side effects are stomach upset, nausea, diarrhea, constipation, heartburn, abdominal pain, and rashes. Vitamin A toxicity at high doses causes dry or peeling skin, skin redness, and hair loss. Most people tolerate echinacea in the short term without problems.
What if I'm allergic to ragweed?
You should be cautious—echinacea can trigger allergic reactions in people sensitive to ragweed and related plants (chrysanthemums, marigolds, daisies). Reactions can range from mild rash and runny nose to severe breathing problems or anaphylaxis in rare cases. If you're in this group, avoid this product unless your doctor has cleared it.
Does this product contain any fillers?
Yes, it contains three inactive ingredients: vegetable cellulose, vegetable magnesium stearate, and water. These are the capsule material and binders, not active ingredients.

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.

Echinacea label
Go deeper

The Full Monographs Behind Echinacea’s Ingredients

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

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

Vitamin A

Interacts with 387 drugs

Vitamin A is an essential nutrient important for vision, skin, immune function, and growth. Most people get enough from a balanced diet, and supplements are mainly useful for correcting a tr...

Read the full Vitamin A monograph →
Sources

Sources & How We Checked

Echinacea'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 82 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.

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.
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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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