Echinacea & Vitamin C Ingredients & Drug Interactions
by Nature's Way
What is this page for?
First and foremost: checking Echinacea & Vitamin C 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
Echinacea & Vitamin C is a dietary supplement by Nature's Way with 2 active ingredients. Its ingredients are commonly taken for common cold and immune support, antioxidant support, skin health and collagen formation.Based on those ingredients, 889 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Echinacea purpurea, Vitamin C. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.
Check Your Meds Against Echinacea & Vitamin C by Nature's Way
Ask about any prescription or over-the-counter medication and we check it for interactions with Echinacea & Vitamin C by Nature's Way — and tell you which ingredient is responsible.
AI summaries are generated from our interaction database for education only — always confirm with your pharmacist. How we use AI
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HelloPharmacist Scorecard of Echinacea & Vitamin C by Nature's Way
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.
What’s inside
Full disclosure
This capsule contains 2 active ingredients: vitamin C and echinacea purpurea (a flowering plant from the daisy family). Vitamin C is a water-soluble vitamin essential for immune function, collagen formation, and antioxidant protection.
Echinacea purpurea has been traditionally used to support immune response. The capsule itself is made from plant-derived material.
Does it work?
Moderate evidence
Vitamin C is effective for preventing and treating vitamin C deficiency, and the evidence suggests it may be possibly effective for anemia of chronic disease, atrial fibrillation, cataracts, and exercise-induced respiratory infections. Echinacea purpurea, however, has insufficient reliable evidence in our data to rate its effectiveness for the conditions it's commonly used for—including anxiety, athletic performance, ADHD, burns, chronic fatigue, and migraine headache.
The evidence for echinacea's benefits simply isn't established well enough to say whether it works for these uses.
How safe is it?
Well-documented data
Vitamin C is generally well tolerated at normal dietary and supplement doses. At very high doses above 2 grams daily, it can cause abdominal cramps, heartburn, osmotic diarrhea, nausea, and vomiting; kidney stones may develop in those prone to them.
Rare serious effects include caroti-related concerns and, with high-dose intravenous use, kidney damage. Echinacea is well tolerated orally in short-term use but may trigger allergic reactions—especially in people sensitive to ragweed or related plants (ragweed, chrysanthemums, marigolds, daisies).
Rare serious effects include hepatitis and severe allergic reactions such as anaphylaxis. Regarding pregnancy and breastfeeding: vitamin C at normal amounts from food and prenatal vitamins is considered fine, but high-dose supplements should be avoided unless your doctor directs otherwise.
For echinacea, pregnancy safety is possibly safe, but there is not enough information on lactation—talk with your doctor or pharmacist for personalized guidance.
Meds to double-check
Moderate interaction found
Before taking this product, check with your doctor or pharmacist if you take oral contraceptives or hormone replacement therapy (estrogen levels may increase substantially), warfarin or other blood thinners (vitamin C may reduce effectiveness, echinacea may increase clearance), chemotherapy drugs (vitamin C's antioxidant effects may reduce drug activity; echinacea may raise etoposide levels), levothyroxine or other thyroid medication (vitamin C increases absorption), immunosuppressants (echinacea may interfere), or caffeine-containing medications or heavy caffeine use (echinacea may raise caffeine levels by around 30%). Additionally, if you take drugs metabolized by your liver's CYP1A2 or CYP3A4 enzymes—a broad category including many HIV antiretrovirals, benzodiazepines, and others—discuss this product with your pharmacist, as echinacea has variable effects on these pathways.
The bottom line
Scorecard at a glanceFully disclosed formula with some supporting evidence for its stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.
This combination is best for people who want vitamin C's well-established benefits (especially preventing deficiency) alongside echinacea, though echinacea's effectiveness for common claims remains unproven in our data. Anyone on birth control, hormone therapy, warfarin, chemotherapy, thyroid medication, or immunosuppressants should absolutely check their exact medications with their doctor or pharmacist before starting.
Ragweed-allergic individuals should be aware of echinacea's potential to trigger reactions.
Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI
Assessment coverage: 2 of 2 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Jul 27, 2021.
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
General information
Key facts about Echinacea & Vitamin C, straight from the product label.
| Brand | Nature's Way |
|---|---|
| Barcode (UPC) | 033674004173 |
| Net contents | 100 Vegan Capsule(s) |
| Market status | On market |
| Date entered into DSLD | Jul 27, 2021 |
| DSLD ID | 251555 |
| Product type | Botanical With Nutrients |
| Supplement form | Capsule |
| Dietary claims / uses | Nutrient, All Other, Structure/Function |
| Intended target group(s) | Vegan, Vegetarian, Adult (18 - 50 Years), Gluten Free, Dairy Free, Sugar Free |
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 & Vitamin C by Nature's Way, sourced from the NIH Dietary Supplement Label Database.
Supplement Facts
| Ingredient | Amount | % DV |
|---|---|---|
| Vitamin C | 200 mg | 222% |
| Echinacea purpurea | 722 mg | -- |
Other ingredients: plant-derived Capsule
Tap any ingredient to jump to its full detail below.
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
Supports Immune System Echinacea has been used by Native Americans for centuries and is native to North America. We combine it with Vitamin C to create a blend specially designed to support immune function.
Premium blend
Gluten free. No sugar, salt, yeast, wheat, soy, dairy products, or artificial colors, flavors, or preservatives.
Vegan
FDA Disclaimer Statement
These statements have not been evaluated by the Food & Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
General Statements
Since 1969
Bottles made from 97% post-consumer recycled plastic
FDA Statement of Identity
Dietary Supplement
Suggested/Recommended/Usage/Directions
Recommendation: Take 2 capsules three times daily, preferably with a meal.
Precautions
Caution: Not recommended for individuals with autoimmune conditions.
Individuals with allergies to plants of the Asteraceae (Compositae) family, including ragweed, should use this product with caution.
If you are pregnant, nursing, or taking any medications, consult a healthcare professional before use.
Keep out of reach of children.
Safety sealed with printed inner seal. Do not use if seal is broken or missing.
Brand IP Statement(s)
Copyright 2019 Nature's Way Brands, LLC
Seals/Symbols
Quality Global Sourcing Bottled & tested in the USA
Formula
Echinacea & Vitamin C 922 mg per serving
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
Echinacea & Vitamin C by Nature's Way label
The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.
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)The Ingredients in Echinacea & Vitamin C by Nature's Way
These are the 2 active ingredients this product is made of. Select any to open its full monograph.
Serving size2 Capsule(s) Dosage formCapsule Servings per container50 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.
Vitamin C
Interacts with207 drugs
Vitamin C (ascorbic acid) is an essential nutrient your body needs but cannot make, so you must get it from food or supplements. It's important for im...
Vitamin C monograph & interactionsEchinacea purpurea
Interacts with816 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 bes...
Echinacea purpurea monograph & interactionsOther (inactive) ingredients: Plant-derived Capsule. These complete the product’s ingredient list but are not active constituents.
Echinacea & Vitamin C by Nature's Way Drug Interactions
HelloPharmacist Interaction Report
Echinacea & Vitamin C by Nature's Way does interact with medications, through both its vitamin C and echinacea purpurea content.
The most serious documented interaction is Moderate in severity: vitamin C can increase blood levels of estrogens, potentially raising plasma estrogen by up to 55% when taken with oral contraceptives or hormone replacement therapy, including topical products.
Read the full breakdown — every affected drug type, severity by severity
Vitamin C also carries Moderate interactions with several drug types. It may reduce the effectiveness of chemotherapy drugs that work by generating free radicals (such as alkylating agents and antitumor antibiotics), increase aluminum absorption from aluminum compounds, reduce warfarin effectiveness at high doses, lower fluphenazine levels, modestly reduce indinavir levels, and increase levothyroxine absorption—which can affect thyroid hormone balance.
Echinacea purpurea adds its own Moderate interactions: it may inhibit metabolism of CYP1A2 substrates (including caffeine, which it can raise by around 30%) and has variable effects on CYP3A4 substrates, potentially raising levels of some drugs like etoposide. It may also interfere with immunosuppressant therapy because of its immune-boosting activity.
Additionally, echinacea carries Minor interactions with warfarin, lopinavir/ritonavir, and midazolam.
Altogether, these interactions span 890 individual medications. Use the interaction checker below to look up your exact prescriptions before starting this product.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against Echinacea & Vitamin C?
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 checkerIngredients driving the most interactions
Individual Drug Interactions
The ingredients in Echinacea & Vitamin C interact with 889 drugs. Click any drug to see the details.
2 of the 2 ingredients in Echinacea & Vitamin C interact with drugs. Each result below shows which ingredient is responsible. Echinacea purpurea Vitamin C
6-mercaptopurinePurinethol
How 6-mercaptopurine interacts with Echinacea & Vitamin C — through 1 ingredient. Tap an ingredient for the detail:
Echinacea PurpureaImmunosuppressants Moderate
Interaction Summary
Echinacea has immunostimulant activity which may interfere with immunosuppressant therapy.
Read the full Echinacea Purpurea + 6-mercaptopurine interactionAdo-trastuzumab EmtansineKadcyla
How Ado-trastuzumab Emtansine interacts with Echinacea & Vitamin C — through 1 ingredient. Tap an ingredient for the detail:
Echinacea PurpureaCytochrome P450 3a4 (cyp3a4) Substrates Moderate
Interaction Summary
Echinacea may induce hepatic CYP3A4 and inhibit intestinal CYP3A4.
Read the full Echinacea Purpurea + Ado-trastuzumab Emtansine interactionAbemaciclibVerzenio
How Abemaciclib interacts with Echinacea & Vitamin C — through 1 ingredient. Tap an ingredient for the detail:
Echinacea PurpureaCytochrome P450 3a4 (cyp3a4) Substrates Moderate
Interaction Summary
Echinacea may induce hepatic CYP3A4 and inhibit intestinal CYP3A4.
Read the full Echinacea Purpurea + Abemaciclib interactionAbiraterone
How Abiraterone interacts with Echinacea & Vitamin C — through 1 ingredient. Tap an ingredient for the detail:
Echinacea PurpureaCytochrome P450 3a4 (cyp3a4) Substrates Moderate
Interaction Summary
Echinacea may induce hepatic CYP3A4 and inhibit intestinal CYP3A4.
Read the full Echinacea Purpurea + Abiraterone interactionAbiraterone AcetateYonsa, Zytiga
How Abiraterone Acetate interacts with Echinacea & Vitamin C — through 1 ingredient. Tap an ingredient for the detail:
Echinacea PurpureaCytochrome P450 3a4 (cyp3a4) Substrates Moderate
Interaction Summary
Echinacea may induce hepatic CYP3A4 and inhibit intestinal CYP3A4.
Read the full Echinacea Purpurea + Abiraterone Acetate interactionAbrocitinibCibinqo
How Abrocitinib interacts with Echinacea & Vitamin C — through 1 ingredient. Tap an ingredient for the detail:
Echinacea PurpureaImmunosuppressants Moderate
Interaction Summary
Echinacea has immunostimulant activity which may interfere with immunosuppressant therapy.
Read the full Echinacea Purpurea + Abrocitinib interactionAcalabrutinibCalquence
How Acalabrutinib interacts with Echinacea & Vitamin C — through 1 ingredient. Tap an ingredient for the detail:
Echinacea PurpureaCytochrome P450 3a4 (cyp3a4) Substrates Moderate
Interaction Summary
Echinacea may induce hepatic CYP3A4 and inhibit intestinal CYP3A4.
Read the full Echinacea Purpurea + Acalabrutinib interactionAcetaminophenChildren's Tylenol, Children's Tylenol Meltaways, Tylenol, Tylenol Ex Strength
How Acetaminophen interacts with Echinacea & Vitamin C — through 2 ingredients. Tap an ingredient for the detail:
Echinacea PurpureaCytochrome P450 1a2 (cyp1a2) Substrates Moderate
Interaction Summary
Echinacea might inhibit the metabolism of CYP1A2 and increase plasma levels of some drugs.
Read the full Echinacea Purpurea + Acetaminophen interactionVitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen interactionAcetaminophen, AspirinGemnisyn
How Acetaminophen, Aspirin interacts with Echinacea & Vitamin C — through 2 ingredients. Tap an ingredient for the detail:
Echinacea PurpureaCytochrome P450 1a2 (cyp1a2) Substrates Moderate
Interaction Summary
Echinacea might inhibit the metabolism of CYP1A2 and increase plasma levels of some drugs.
Read the full Echinacea Purpurea + Acetaminophen, Aspirin interactionVitamin CAcetaminophen (tylenol, Others), Aspirin Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Aspirin interactionAcetaminophen, Aspirin, CaffeineExcedrin, Excedrin Extra Strength, Excedrin Migraine
How Acetaminophen, Aspirin, Caffeine interacts with Echinacea & Vitamin C — through 2 ingredients. Tap an ingredient for the detail:
Echinacea PurpureaCaffeine, Cytochrome P450 1a2 (cyp1a2) Substrates +1 Moderate
Interaction Summary
Echinacea can increase plasma levels of caffeine by inhibiting its metabolism.
Read the full Echinacea Purpurea + Acetaminophen, Aspirin, Caffeine interactionVitamin CAspirin, Acetaminophen (tylenol, Others) Minor
Interaction Summary
Acidification of the urine by vitamin C might increase aspirin levels.
Read the full Vitamin C + Acetaminophen, Aspirin, Caffeine interactionAcetaminophen, Brompheniramine, PhenylpropanolamineDimetapp Cold and Flu
How Acetaminophen, Brompheniramine, Phenylpropanolamine interacts with Echinacea & Vitamin C — through 2 ingredients. Tap an ingredient for the detail:
Echinacea PurpureaCytochrome P450 1a2 (cyp1a2) Substrates Moderate
Interaction Summary
Echinacea might inhibit the metabolism of CYP1A2 and increase plasma levels of some drugs.
Read the full Echinacea Purpurea + Acetaminophen, Brompheniramine, Phenylpropanolamine interactionVitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Brompheniramine, Phenylpropanolamine interactionAcetaminophen, ButalbitalAxocet, Bancap, Bucet, Butex Forte, Esgic CF, Orbivan CF +5 more
How Acetaminophen, Butalbital interacts with Echinacea & Vitamin C — through 2 ingredients. Tap an ingredient for the detail:
Echinacea PurpureaCytochrome P450 1a2 (cyp1a2) Substrates Moderate
Interaction Summary
Echinacea might inhibit the metabolism of CYP1A2 and increase plasma levels of some drugs.
Read the full Echinacea Purpurea + Acetaminophen, Butalbital interactionVitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Butalbital interactionAcetaminophen, Butalbital, CaffeineEsgic, Esgic Plus, Fiogesic, Fioricet, Repan, Tecnal +1 more
How Acetaminophen, Butalbital, Caffeine interacts with Echinacea & Vitamin C — through 2 ingredients. Tap an ingredient for the detail:
Echinacea PurpureaCytochrome P450 1a2 (cyp1a2) Substrates, Cytochrome P450 3a4 (cyp3a4) Substrates +1 Moderate
Interaction Summary
Echinacea might inhibit the metabolism of CYP1A2 and increase plasma levels of some drugs.
Read the full Echinacea Purpurea + Acetaminophen, Butalbital, Caffeine interactionVitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Butalbital, Caffeine interactionAcetaminophen, Butalbital, Caffeine, CodeineEsgic with Codeine, Fioricet w/ Codeine
How Acetaminophen, Butalbital, Caffeine, Codeine interacts with Echinacea & Vitamin C — through 2 ingredients. Tap an ingredient for the detail:
Echinacea PurpureaCaffeine, Cytochrome P450 1a2 (cyp1a2) Substrates +1 Moderate
Interaction Summary
Echinacea can increase plasma levels of caffeine by inhibiting its metabolism.
Read the full Echinacea Purpurea + Acetaminophen, Butalbital, Caffeine, Codeine interactionVitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Butalbital, Caffeine, Codeine interactionAcetaminophen, Butalbital, CodeineBancap w/ Codeine
How Acetaminophen, Butalbital, Codeine interacts with Echinacea & Vitamin C — through 2 ingredients. Tap an ingredient for the detail:
Echinacea PurpureaCytochrome P450 1a2 (cyp1a2) Substrates Moderate
Interaction Summary
Echinacea might inhibit the metabolism of CYP1A2 and increase plasma levels of some drugs.
Read the full Echinacea Purpurea + Acetaminophen, Butalbital, Codeine interactionVitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Butalbital, Codeine interactionAcetaminophen, Butalbital, Codeine PhosphatePhrenilin #3
How Acetaminophen, Butalbital, Codeine Phosphate interacts with Echinacea & Vitamin C — through 2 ingredients. Tap an ingredient for the detail:
Echinacea PurpureaCytochrome P450 1a2 (cyp1a2) Substrates Moderate
Interaction Summary
Echinacea might inhibit the metabolism of CYP1A2 and increase plasma levels of some drugs.
Read the full Echinacea Purpurea + Acetaminophen, Butalbital, Codeine Phosphate interactionVitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Butalbital, Codeine Phosphate interactionAcetaminophen, Caffeine, Chlorpheniramine, Hydrocodone, PhenylephrineHycomine Compound
How Acetaminophen, Caffeine, Chlorpheniramine, Hydrocodone, Phenylephrine interacts with Echinacea & Vitamin C — through 2 ingredients. Tap an ingredient for the detail:
Echinacea PurpureaCaffeine, Cytochrome P450 1a2 (cyp1a2) Substrates +1 Moderate
Interaction Summary
Echinacea can increase plasma levels of caffeine by inhibiting its metabolism.
Read the full Echinacea Purpurea + Acetaminophen, Caffeine, Chlorpheniramine, Hydrocodone, Phenylephrine interactionVitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Caffeine, Chlorpheniramine, Hydrocodone, Phenylephrine interactionAcetaminophen, Caffeine, CodeineGesic C15, Gesic C30, Gesic C8, Lenoltec 1, Lenoltec 2, Lenoltec 3 +1 more
How Acetaminophen, Caffeine, Codeine interacts with Echinacea & Vitamin C — through 2 ingredients. Tap an ingredient for the detail:
Echinacea PurpureaCytochrome P450 1a2 (cyp1a2) Substrates, Cytochrome P450 3a4 (cyp3a4) Substrates +1 Moderate
Interaction Summary
Echinacea might inhibit the metabolism of CYP1A2 and increase plasma levels of some drugs.
Read the full Echinacea Purpurea + Acetaminophen, Caffeine, Codeine interactionVitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Caffeine, Codeine interactionAcetaminophen, Caffeine, Codeine, SalicylamideCodalan No.1, Codalan No.2, Codalan No.3
How Acetaminophen, Caffeine, Codeine, Salicylamide interacts with Echinacea & Vitamin C — through 2 ingredients. Tap an ingredient for the detail:
Echinacea PurpureaCaffeine, Cytochrome P450 3a4 (cyp3a4) Substrates +1 Moderate
Interaction Summary
Echinacea can increase plasma levels of caffeine by inhibiting its metabolism.
Read the full Echinacea Purpurea + Acetaminophen, Caffeine, Codeine, Salicylamide interactionVitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Caffeine, Codeine, Salicylamide interactionAcetaminophen, Caffeine, DihydrocodeineDHC Plus, Panlor DC, Panlor SS
How Acetaminophen, Caffeine, Dihydrocodeine interacts with Echinacea & Vitamin C — through 2 ingredients. Tap an ingredient for the detail:
Echinacea PurpureaCytochrome P450 1a2 (cyp1a2) Substrates, Caffeine +1 Moderate
Interaction Summary
Echinacea might inhibit the metabolism of CYP1A2 and increase plasma levels of some drugs.
Read the full Echinacea Purpurea + Acetaminophen, Caffeine, Dihydrocodeine interactionVitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Caffeine, Dihydrocodeine interactionAcetaminophen, Caffeine, IsomethepteneMigralam
How Acetaminophen, Caffeine, Isometheptene interacts with Echinacea & Vitamin C — through 2 ingredients. Tap an ingredient for the detail:
Echinacea PurpureaCytochrome P450 3a4 (cyp3a4) Substrates, Cytochrome P450 1a2 (cyp1a2) Substrates +1 Moderate
Interaction Summary
Echinacea may induce hepatic CYP3A4 and inhibit intestinal CYP3A4.
Read the full Echinacea Purpurea + Acetaminophen, Caffeine, Isometheptene interactionVitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Caffeine, Isometheptene interactionAcetaminophen, Caffeine, PyrilamineMidol Max Strength Menstrual
How Acetaminophen, Caffeine, Pyrilamine interacts with Echinacea & Vitamin C — through 2 ingredients. Tap an ingredient for the detail:
Echinacea PurpureaCaffeine, Cytochrome P450 3a4 (cyp3a4) Substrates +1 Moderate
Interaction Summary
Echinacea can increase plasma levels of caffeine by inhibiting its metabolism.
Read the full Echinacea Purpurea + Acetaminophen, Caffeine, Pyrilamine interactionVitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Caffeine, Pyrilamine interactionAcetaminophen, Chlorpheniramine Maleate, Dextromethorphan HbrVicks Formula 44M Cough, Cold & Flu Relief
How Acetaminophen, Chlorpheniramine Maleate, Dextromethorphan Hbr interacts with Echinacea & Vitamin C — through 2 ingredients. Tap an ingredient for the detail:
Echinacea PurpureaCytochrome P450 1a2 (cyp1a2) Substrates, Cytochrome P450 3a4 (cyp3a4) Substrates Moderate
Interaction Summary
Echinacea might inhibit the metabolism of CYP1A2 and increase plasma levels of some drugs.
Read the full Echinacea Purpurea + Acetaminophen, Chlorpheniramine Maleate, Dextromethorphan Hbr interactionVitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Chlorpheniramine Maleate, Dextromethorphan Hbr interactionAcetaminophen, Chlorpheniramine, Codeine, PhenylephrineColrex
How Acetaminophen, Chlorpheniramine, Codeine, Phenylephrine interacts with Echinacea & Vitamin C — through 2 ingredients. Tap an ingredient for the detail:
Echinacea PurpureaCytochrome P450 1a2 (cyp1a2) Substrates, Cytochrome P450 3a4 (cyp3a4) Substrates Moderate
Interaction Summary
Echinacea might inhibit the metabolism of CYP1A2 and increase plasma levels of some drugs.
Read the full Echinacea Purpurea + Acetaminophen, Chlorpheniramine, Codeine, Phenylephrine interactionVitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Chlorpheniramine, Codeine, Phenylephrine interactionAcetaminophen, Chlorpheniramine, DextromethorphanCoricidin II Extra Strength Cold and Flu
How Acetaminophen, Chlorpheniramine, Dextromethorphan interacts with Echinacea & Vitamin C — through 2 ingredients. Tap an ingredient for the detail:
Echinacea PurpureaCytochrome P450 3a4 (cyp3a4) Substrates, Cytochrome P450 1a2 (cyp1a2) Substrates Moderate
Interaction Summary
Echinacea may induce hepatic CYP3A4 and inhibit intestinal CYP3A4.
Read the full Echinacea Purpurea + Acetaminophen, Chlorpheniramine, Dextromethorphan interactionVitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Chlorpheniramine, Dextromethorphan interactionAcetaminophen, Chlorpheniramine, Dextromethorphan HydrobromideCoricidin HBP Maximum Strength Flu
How Acetaminophen, Chlorpheniramine, Dextromethorphan Hydrobromide interacts with Echinacea & Vitamin C — through 2 ingredients. Tap an ingredient for the detail:
Echinacea PurpureaCytochrome P450 1a2 (cyp1a2) Substrates, Cytochrome P450 3a4 (cyp3a4) Substrates Moderate
Interaction Summary
Echinacea might inhibit the metabolism of CYP1A2 and increase plasma levels of some drugs.
Read the full Echinacea Purpurea + Acetaminophen, Chlorpheniramine, Dextromethorphan Hydrobromide interactionVitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Chlorpheniramine, Dextromethorphan Hydrobromide interactionAcetaminophen, Chlorpheniramine, Dextromethorphan, PhenylpropanolamineMulti Symptom Cold Relief
How Acetaminophen, Chlorpheniramine, Dextromethorphan, Phenylpropanolamine interacts with Echinacea & Vitamin C — through 2 ingredients. Tap an ingredient for the detail:
Echinacea PurpureaCytochrome P450 1a2 (cyp1a2) Substrates, Cytochrome P450 3a4 (cyp3a4) Substrates Moderate
Interaction Summary
Echinacea might inhibit the metabolism of CYP1A2 and increase plasma levels of some drugs.
Read the full Echinacea Purpurea + Acetaminophen, Chlorpheniramine, Dextromethorphan, Phenylpropanolamine interactionVitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Chlorpheniramine, Dextromethorphan, Phenylpropanolamine interactionAcetaminophen, Chlorpheniramine, Dextromethorphan, PseudoephedrineChildren's Tylenol Cold Plus Cough, Tylenol Cold Ex Strength
How Acetaminophen, Chlorpheniramine, Dextromethorphan, Pseudoephedrine interacts with Echinacea & Vitamin C — through 2 ingredients. Tap an ingredient for the detail:
Echinacea PurpureaCytochrome P450 1a2 (cyp1a2) Substrates, Cytochrome P450 3a4 (cyp3a4) Substrates Moderate
Interaction Summary
Echinacea might inhibit the metabolism of CYP1A2 and increase plasma levels of some drugs.
Read the full Echinacea Purpurea + Acetaminophen, Chlorpheniramine, Dextromethorphan, Pseudoephedrine interactionVitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Chlorpheniramine, Dextromethorphan, Pseudoephedrine interactionAcetaminophen, Chlorpheniramine, Guaifenesin, Phenylephrine, SalicylamideRhinogesic GG
How Acetaminophen, Chlorpheniramine, Guaifenesin, Phenylephrine, Salicylamide interacts with Echinacea & Vitamin C — through 2 ingredients. Tap an ingredient for the detail:
Echinacea PurpureaCytochrome P450 3a4 (cyp3a4) Substrates, Cytochrome P450 1a2 (cyp1a2) Substrates Moderate
Interaction Summary
Echinacea may induce hepatic CYP3A4 and inhibit intestinal CYP3A4.
Read the full Echinacea Purpurea + Acetaminophen, Chlorpheniramine, Guaifenesin, Phenylephrine, Salicylamide interactionVitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Chlorpheniramine, Guaifenesin, Phenylephrine, Salicylamide interactionAcetaminophen, Chlorpheniramine, PhenylephrineAlka-Seltzer PLUS, Histex SR, Protid
How Acetaminophen, Chlorpheniramine, Phenylephrine interacts with Echinacea & Vitamin C — through 2 ingredients. Tap an ingredient for the detail:
Echinacea PurpureaCytochrome P450 1a2 (cyp1a2) Substrates, Cytochrome P450 3a4 (cyp3a4) Substrates Moderate
Interaction Summary
Echinacea might inhibit the metabolism of CYP1A2 and increase plasma levels of some drugs.
Read the full Echinacea Purpurea + Acetaminophen, Chlorpheniramine, Phenylephrine interactionVitamin CAcetaminophen (tylenol, Others) Minor
Interaction Summary
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Read the full Vitamin C + Acetaminophen, Chlorpheniramine, Phenylephrine interactionEach ingredient & the kinds of drugs it affects
For each ingredient in Echinacea & Vitamin C 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 purpurea
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.
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.
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.
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.
Immunosuppressants
Echinacea has immunostimulant activity which may interfere with immunosuppressant therapy.
Theoretically, echinacea may interfere with immunosuppressant therapy because of its immunostimulant activity.
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.
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.
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.
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.
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.
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.
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.
Vitamin C
Alkylating Agents
Theoretically, antioxidant effects of vitamin C might reduce the effectiveness of alkylating agents.
The use of antioxidants like vitamin C during chemotherapy is controversial. There is concern that antioxidants could reduce the activity of chemotherapy drugs that generate free radicals, such as cyclophosphamide, chlorambucil, carmustine, busulfan, and thiotepa. In contrast, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that could interfere with apoptosis (cell death) of cancer cells. More evidence is needed to determine what effect, if any, antioxidants such as vitamin C have on chemotherapy.
Aluminum
Vitamin C can increase the amount of aluminum absorbed from aluminum compounds.
Research in animals and humans shows that vitamin C increases aluminum absorption, theoretically by chelating aluminum and keeping it in solution where it is available for absorption. In people with normal renal function, urinary excretion of aluminum will likely increase, making aluminum retention and toxicity unlikely. Patients with renal failure who take aluminum-containing compounds such as phosphate binders should avoid vitamin C supplements in doses above the recommended dietary allowances.
Antitumor Antibiotics
Theoretically, the antioxidant effects of vitamin C might reduce the effectiveness of antitumor antibiotics.
The use of antioxidants like vitamin C during chemotherapy is controversial. There is concern that antioxidants could reduce the activity of chemotherapy drugs which generate free radicals, such as doxorubicin. In contrast, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that could interfere with apoptosis (cell death) of cancer cells. More evidence is needed to determine what effects, if any, antioxidants such as vitamin C have on chemotherapy.
Estrogens
Vitamin C might increase blood levels of estrogens.
Increases in plasma estrogen levels of up to 55% occur under some circumstances when vitamin C is taken concurrently with oral contraceptives or hormone replacement therapy, including topical products. It is suggested that vitamin C prevents oxidation of estrogen in the tissues, regenerates oxidized estrogen, and reduces sulfate conjugation of estrogen in the gut wall. When tissue levels of vitamin C are high, these processes are already maximized and supplemental vitamin C does not have any effect on estrogen levels. Increases in plasma estrogen levels may occur when patients who are deficient in vitamin C take supplements. Monitor these patients for estrogen-related side effects.
Fluphenazine (Prolixin)
Theoretically, vitamin C might decrease levels of fluphenazine.
In one patient there was a clinically significant decrease in fluphenazine levels when vitamin C (500 mg twice daily) was started. The mechanism is not known, and there is no further data to confirm this interaction.
Indinavir (Crixivan)
Vitamin C can modestly reduce indinavir levels.
One pharmacokinetic study shows that taking vitamin C 1 gram orally once daily along with indinavir 800 mg orally three times daily reduces the area under the concentration-time curve of indinavir by 14%. The mechanism of this interaction is unknown, but it is unlikely to be clinically significant in most patients. The effect of higher doses of vitamin C on indinavir levels is unknown.
Levothyroxine (Synthroid, Others)
Vitamin C can increase levothyroxine absorption.
Two clinical studies in adults with poorly controlled hypothyroidism show that swallowing levothyroxine with a glass of water containing vitamin C 500-1000 mg in solution reduces thyroid stimulating hormone (TSH) levels and increases thyroxine (T4) levels when compared with taking levothyroxine alone. This suggests that vitamin C increases the oral absorption of levothyroxine, possibly due to a reduction in pH.
Warfarin (Coumadin)
High-dose vitamin C might reduce the levels and effectiveness of warfarin.
Vitamin C in high doses may cause diarrhea and possibly reduce warfarin absorption. There are reports of two people who took up to 16 grams daily of vitamin C and had a reduction in prothrombin time. Lower doses of 5-10 grams daily can also reduce warfarin absorption. In many cases, this does not seem to be clinically significant. However, a case of warfarin resistance has been reported for a patient who took vitamin C 500 mg twice daily. Cessation of vitamin C supplementation resulted in a rapid increase in international normalized ratio (INR). Tell patients taking warfarin to avoid taking vitamin C in excessively high doses (greater than 10 grams daily). Lower doses may be safe, but the anticoagulation activity of warfarin should be monitored. Patients who are stabilized on warfarin while taking vitamin C should avoid adjusting vitamin C dosage to prevent the possibility of warfarin resistance.
Acetaminophen (Tylenol, Others)
High-dose vitamin C might slightly prolong the clearance of acetaminophen.
A small pharmacokinetic study in healthy volunteers shows that taking high-dose vitamin C (3 grams) 1.5 hours after taking acetaminophen 1 gram slightly increases the apparent half-life of acetaminophen from around 2.3 hours to 3.1 hours. Ascorbic acid competitively inhibits sulfate conjugation of acetaminophen. However, to compensate, elimination of acetaminophen glucuronide and unconjugated acetaminophen increases. This effect is not likely to be clinically significant.
Aspirin
Acidification of the urine by vitamin C might increase aspirin levels.
It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels. However, short-term use of up to 6 grams daily of vitamin C does not seem to affect urinary pH or salicylate excretion, suggesting this interaction is not clinically significant.
Choline Magnesium Trisalicylate (Trilisate)
Acidification of the urine by vitamin C might increase choline magnesium trisalicylate levels.
It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels. However, short-term use of up to 6 grams daily of vitamin C does not seem to affect urinary pH or salicylate excretion, suggesting this interaction probably is not clinically significant.
Niacin
Vitamin C might decrease the beneficial effects of niacin on high-density lipoprotein (HDL) cholesterol levels.
A combination of niacin and simvastatin (Zocor) effectively raises HDL cholesterol levels in patients with coronary disease and low HDL levels. Clinical research shows that taking a combination of antioxidants (vitamin C, vitamin E, beta-carotene, and selenium) along with niacin and simvastatin (Zocor) attenuates this rise in HDL, specifically the HDL-2 and apolipoprotein A1 fractions, by more than 50% in patients with coronary disease. It is not known whether this adverse effect is due to a single antioxidant such as vitamin C, or to the combination. It also is not known whether it will occur in other patient populations.
Salsalate (Disalcid)
Acidification of the urine by vitamin C might increase salsalate levels.
It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels. However, short-term use of up to 6 grams/day vitamin C does not seem to affect urinary pH or salicylate excretion, suggesting this interaction probably is not clinically significant.
Brand information
Manufacturer and brand details for Echinacea & Vitamin C, from the product label.
Nature's Way
See all Nature's Way products- Name
- Nature's Way Brands, LLC
- City
- Green Bay
- State
- WI
- ZipCode
- 54311
- Phone Number
- 1-800-962-8873
- Web Address
- naturesway.com
Echinacea & Vitamin C by Nature's Way: Common Questions
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The Full Monographs Behind Echinacea & Vitamin C’s Ingredients
Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.
Vitamin C
Interacts with 207 drugsVitamin C (ascorbic acid) is an essential nutrient your body needs but cannot make, so you must get it from food or supplements. It's important for immune function, collagen, and acts as an...
Read the full Vitamin C monograph → Herb & supplement monographEchinacea
Interacts with 816 drugsEchinacea 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 →Sources & How We Checked
Echinacea & Vitamin C'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.
- NIH Dietary Supplement Label Database (DSLD) — The official product label on file for this supplement.
- Natural Medicines (Therapeutic Research Center) — Evidence-graded clinical reference behind the ingredient interaction data.
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 102 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.
Vitamin C 51 references
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Echinacea 51 references
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- 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
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- Soon SL, Crawford RI. Recurrent erythema nodosum associated with echinacea herbal therapy. J Am Acad Dermatol 2001;44:298-9. PubMed
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- 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.
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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.
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