Interactions on record — worth a quick check against your medications. Based on 3 of 5 ingredients. Check your meds →
Dietary supplement

Immune Boost Herbal Blend Ingredients & Drug Interactions

by Nature's Answer

Immune Boost Herbal Blend label
See full label image
Liquid 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 Immune Boost Herbal Blend 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

Immune Boost Herbal Blend is a dietary supplement by Nature's Answer with 5 active ingredients. Its ingredients are commonly taken for common cold, flu and respiratory infections, immune support.Based on those ingredients, 1,118 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Echinacea angustifolia root extract, Thuja occidentalis aerial parts extract. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Immune Boost Herbal Blend by Nature's Answer

Ask about any prescription or over-the-counter medication and we check it for interactions with Immune Boost Herbal Blend by Nature's Answer — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Immune Boost Herbal Blend by Nature's Answer

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 11, 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 0 of its 5 active ingredients.
  • “Proprietary Herbal Extract Blend” is a proprietary blend — the label gives one combined amount (2,000 mg) without saying how much of each component you get.

This product has 5 active ingredients working together. Three are echinacea — echinacea angustifolia root, echinacea purpurea root, and echinacea purpurea aerial parts — which are traditionally used as immune support.

The fourth is thuja occidentalis aerial parts extract, also used for immune support. The fifth is olive leaf extract.

All are plant extracts. The product also contains vegetable glycerin, purified water, and citric acid as inactive ingredients to deliver the blend in liquid form.

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: Supports a healthy immune system.
  • We looked for evidence on: Common cold, Influenza, Upper respiratory tract infection (URTI), Exercise-induced respiratory infections, Coronavirus disease 2019 (COVID-19), Immune function — and 2 related terms.
  • The closest evidence on file: Olive is rated "Insufficient Reliable Evidence To Rate" for Exercise-induced respiratory infections (Natural Medicines).
  • Also on file: Olive is rated "Insufficient Reliable Evidence To Rate" for Influenza.
  • Also on file: Echinacea is rated "Insufficient Reliable Evidence To Rate" for Upper respiratory tract infection (URTI), Influenza, Coronavirus disease 2019 (COVID-19).

The evidence on these ingredients is limited. For the echinacea extracts and thuja, we hold insufficient reliable evidence to rate their effectiveness for anxiety, athletic performance, ADHD, burns, chronic fatigue syndrome, or migraine headache.

Olive leaf extract shows insufficient reliable evidence for osteoporosis, indigestion (dyspepsia), exercise-related respiratory infections, shingles, flu, or osteoarthritis. The data we have doesn't establish how well any of these work for immune support specifically.

The evidence, ingredient by ingredient Echinacea Olive Thuja

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.

Echinacea is generally well tolerated short-term, but allergic reactions are possible, especially if you're sensitive to ragweed or related plants like chrysanthemums, marigolds, or daisies. Most common side effects are mild — abdominal pain, diarrhea, heartburn, nausea, and rashes.

Rare severe allergic reactions and liver inflammation have been reported. Olive leaf extract is generally well tolerated; headache and stomach discomfort are the most common effects, though one person reported acne.

Thuja is different — it contains thujone, a neurotoxin, and large doses can cause nervous agitation, seizures, and organ damage. Thuja should be avoided in pregnancy (likely unsafe) and while breastfeeding (likely unsafe).

For echinacea, pregnancy safety is rated possibly safe, but lactation data isn't available. For olive leaf, pregnancy and lactation data isn't on file.

Side effects, ingredient by ingredient Echinacea Olive Thuja

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 — Echinacea, Thuja.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; seizure medications; immunosuppressants / transplant drugs.
  • For scale: 1,119 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, double-check with your pharmacist if you take seizure medications or seizure-threshold-lowering anesthetics (Moderate); blood thinners like warfarin (Minor); any immunosuppressant drugs (Moderate); cancer drugs like etoposide (Moderate); or drugs metabolized by your liver through the CYP1A2 or CYP3A4 pathways, especially HIV medications like lopinavir/ritonavir (Minor). Caffeine levels may also increase by around 30%.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFormula with limited ingredient disclosure with no established evidence rating for its marketed use. Moderate medication interactions have been identified, and safety information is well characterized.

If you take any blood thinners, seizure medications, immunosuppressants, or cancer drugs, talk to your pharmacist or doctor before trying this product — the interactions are real and may affect how your medications work. It's generally well tolerated if you don't have ragweed allergies, but the effectiveness for immune support isn't established.

Don't use if you're pregnant or breastfeeding without checking first.

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

Assessment coverage: 5 of 5 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated May 19, 2022.

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 Immune Boost Herbal Blend, straight from the product label.

Brand Nature's Answer
Barcode (UPC) 083000007989
Net contents 1 fl. Oz.; 30 mL
Market status On market
Date entered into DSLD May 19, 2022
DSLD ID 264018
Product type Botanical
Supplement form Liquid
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Kosher, Women (not pregnant or lactating), Gluten 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 Immune Boost Herbal Blend by Nature's Answer, 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 mL
Maximum serving Sizes:
2 mL
Servings per container
15
UPC/BARCODE
083000007989
IngredientAmount% DV
Proprietary Herbal Extract Blend2000 mg--
Echinacea angustifolia root extract0 NP--
Olive Leaf Extract0 NP--
Echinacea purpurea root extract0 NP--
Echinacea purpurea aerial part extract0 NP--
Thuja occidentalis aerial parts extract0 NP--

Other ingredients: Vegetable Glycerin, Water, Purified, Citric Acid

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.
FDA Disclaimer Statement

This statement has not been evaluated by the FDA. This product is not intended to diagnose, treat, cure, or prevent any disease.

Formulation

Gluten Free

Fluid Extract Supports a Healthy Immune System

Alcohol-Free

Our alcohol-free extracts are produced using our cold Bio-Chelated proprietary extraction process, yielding a Holistically Balanced Advanced Botanical Fingerprint extract in the same synergistic ratios as in the plant.

Seals/Symbols

K Parve (Kosher)

Bio-Chelated Cold Extraction Process

Formula

K Parve (Kosher)

Immune Boost Herbal Blend 2,000 mg per serving

FDA Statement of Identity

Herbal Supplement

Brand IP Statement(s)

Nature's Answer Since 1972

Discover Nature's Answer

Copyright 2020 Nature's Answer

Suggested/Recommended/Usage/Directions

Suggested use: As a dietary supplement, take 1-2 mL (30-61 drops) two (2)-three (3) times a day in a small amount of water. Shake well.

Precautions

Keep out of reach of children.

Warning: Do not use if pregnant or nursing.

Do not use if safety seal is damaged or missing.

Storage

Store in a cool, dry place.

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

See for yourself

Immune Boost Herbal Blend by Nature's Answer label

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

Immune Boost Herbal Blend 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 Immune Boost Herbal Blend by Nature's Answer

These are the 5 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 mL Dosage formLiquid Servings per container15 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.

Other (inactive) ingredients: Vegetable Glycerin, Water, Purified, Citric Acid. These complete the product’s ingredient list but are not active constituents.

Interaction report

Immune Boost Herbal Blend by Nature's Answer Drug Interactions

Want to check YOUR meds against Immune Boost Herbal Blend?

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
1,118Drugs
1,117 Moderate 1 Minor

Ingredients driving the most interactions

Echinacea angustifolia root extract 816
Thuja occidentalis aerial parts extract 576

Individual Drug Interactions

The ingredients in Immune Boost Herbal Blend interact with 1,118 drugs. Click any drug to see the details.

2 of the 5 ingredients in Immune Boost Herbal Blend interact with drugs. Each result below shows which ingredient is responsible. Echinacea angustifolia root extract Thuja occidentalis aerial parts extract

Each ingredient & the kinds of drugs it affects

For each ingredient in Immune Boost Herbal Blend 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 angustifolia root 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 angustifolia root extract full monograph & interactions

Thuja occidentalis aerial parts extract3 drug types · 576 drugs

Anticonvulsants

Thuja products can contain thujone, which might lower the seizure threshold. Theoretically, this could decrease the effectiveness of anticonvulsants drugs.

Likelihood Possible Evidence D
Immunosuppressants

Thuja might stimulate immune function. Theoretically, taking thuja might decrease the effects of immunosuppressive therapy. Immunosuppressant drugs include azathioprine (Imuran), basiliximab (Simulect), cyclosporine (Neoral, Sandimmune), daclizumab (Zenapax), muromonab-CD3 (OKT3, Orthoclone OKT3), mycophenolate (CellCept), tacrolimus (FK506, Prograf), sirolimus (Rapamune), prednisone (Deltasone, Orasone), and other corticosteroids (glucocorticoids).

Likelihood Possible Evidence D
Seizure Threshold Lowering Drugs

Thuja products can contains significant amounts of thujone, a neurotoxin. Theoretically, patients taking drugs that lower the seizure threshold might be at greater risk of seizure if they also take thuja. Advise patients taking these drugs to avoid thuja products. Some drugs that lower the seizure threshold include anesthetics (propofol, others), antiarrhythmics (mexiletine), antibiotics (amphotericin, penicillin, cephalosporins, imipenem), antidepressants (bupropion, others), antihistamines (cyproheptadine, others), immunosuppressants (cyclosporine), narcotics (fentanyl, others), stimulants (methylphenidate), theophylline, and others.

Likelihood Possible Evidence D
Thuja occidentalis aerial parts extract full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Immune Boost Herbal Blend, from the product label.

Nature's Answer

See all Nature's Answer products
Name
Nature's Answer
Street Address
85 Commerce Drive
City
Hauppauge
State
NY
ZipCode
11788
Phone Number
(800) 439-2324
Web Address
www.naturesanswer.com
Pharmacist Counseling Corner

Immune Boost Herbal Blend by Nature's Answer: Common Questions

Does Immune Boost Herbal Blend by Nature's Answer interact with any medications?
Yes. Based on its ingredients, Immune Boost Herbal Blend has a known interaction with 1,118 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Immune Boost Herbal Blend contains 5 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.
Can I use this if I'm pregnant?
Echinacea is rated possibly safe in pregnancy, but thuja is rated likely unsafe and should be avoided — it was traditionally used to trigger miscarriage. Olive leaf data isn't available. Talk with your doctor or pharmacist before using this product if you're pregnant.
Can I breastfeed while taking this?
Thuja is rated likely unsafe while breastfeeding. Echinacea and olive leaf don't have lactation data on file. It's best to ask your pharmacist or doctor before using this product while nursing.
Does this actually help with immunity?
The evidence on echinacea, thuja, and olive leaf for immune support isn't established in the data we hold. There's insufficient reliable evidence to say whether this blend works for that purpose.
What are the most common side effects?
With echinacea and olive leaf, the most common are mild — stomach upset, diarrhea, heartburn, nausea, headache, and rashes. Allergic reactions are possible if you're sensitive to ragweed or related plants.
Is it safe if I'm allergic to ragweed?
No. Echinacea can trigger allergic reactions in people sensitive to ragweed and plants in the daisy family. Avoid this product if you have that sensitivity.

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.

Immune Boost Herbal Blend label
Go deeper

The Full Monographs Behind Immune Boost Herbal Blend’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

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

Thuja

Interacts with 576 drugs

Thuja, also called northern white cedar or arborvitae, is a tree whose leaf and oil have a long history in folk and homeopathic medicine, especially for warts and immune support. Solid human...

Read the full Thuja monograph →
Sources

Sources & How We Checked

Immune Boost Herbal Blend'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 63 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.
  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.
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See these in context on the Echinacea monograph →

Olive 2 references
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See these in context on the Olive monograph →

Thuja 10 references
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  2. McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
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See these in context on the Thuja 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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