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

Pollen Defense Ingredients & Drug Interactions

by Herb Pharm

Pollen Defense 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 Pollen Defense 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

Pollen Defense is a dietary supplement by Herb Pharm with 5 active ingredients. Its ingredients are commonly taken for sinus and respiratory congestion, urinary tract infections, digestive support.Based on those ingredients, 1,254 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Goldenseal Rhizome with Rootlet Extract, Stinging Nettle Seed Extract, Eyebright Flowering Aerial Parts Extract. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Pollen Defense by Herb Pharm

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

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HelloPharmacist Scorecard of Pollen Defense by Herb Pharm

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 Sep 3, 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 Extract Blend” is a proprietary blend — the label gives one combined amount (662 mg) without saying how much of each component you get.

Pollen Defense is a liquid supplement with 5 active ingredients: horseradish root extract, goldenseal rhizome with rootlet extract, stinging nettle seed extract, eyebright flowering aerial parts extract, and yarrow flowering top extract. The product also contains cane alcohol, distilled water, and glycerin as inactive ingredients.

Each of these plant extracts has been traditionally used to support respiratory and immune function, though the strength of evidence varies widely by ingredient and condition.

Does it work?

Insufficient evidence
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
Insufficient

There isn't enough reliable clinical evidence to rate this product's ingredients for its stated purpose.

Why this rating?
  • The label markets this product for: respiratory system and seasonal allergy support.
  • We looked for evidence on: Allergic rhinitis (hay fever), Asthma, Common cold, Cough, Respiratory tract infections, Rhinosinusitis — and 4 related terms.
  • The closest evidence on file: Eyebright is rated "Insufficient Reliable Evidence To Rate" for Allergic rhinitis (hay fever) (Natural Medicines).
  • Also on file: Eyebright is rated "Insufficient Reliable Evidence To Rate" for Common cold, Cough, Rhinosinusitis, Asthenopia (eye strain), and more.
  • Also on file: Horseradish is rated "Insufficient Reliable Evidence To Rate" for Respiratory tract infections.

The evidence for Pollen Defense's ingredients is limited. Horseradish, goldenseal, eyebright, and yarrow all show insufficient reliable evidence for their most common uses — respiratory tract infections, allergic rhinitis (hay fever), cough, and wound healing, among others.

Stinging nettle is rated possibly effective for diabetes, but that's not a primary purpose of this product. Overall, we don't have established evidence that these ingredients work for the conditions Pollen Defense is marketed to address.

The evidence, ingredient by ingredient Horseradish Goldenseal Stinging Nettle Eyebright Yarrow

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 5 of the 5 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 5 of 5.
  • General safety write-ups exist for 5 of 5.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Horseradish is generally well tolerated in food amounts, but large doses can irritate your digestive tract and rarely cause vasovagal syncope (a sudden drop in heart rate and blood pressure). Goldenseal is typically used short-term; human safety data are limited.

Large amounts of horseradish or goldenseal may cause gastrointestinal upset, nausea, vomiting, diarrhea, or headache. Stinging nettle is generally well tolerated for most adults, though constipation and diarrhea have been reported; topical contact with the raw plant causes itching and rash.

Eyebright may cause confusion, headache, nausea, constipation, cough, or nasal congestion. Yarrow is often used short-term and seems well tolerated orally, but can cause allergic dermatitis or urticaria when applied to skin.

During pregnancy, goldenseal, stinging nettle, eyebright, and yarrow are all rated likely unsafe — safety has not been established or there are theoretical concerns about uterine effects. Horseradish should be limited to food amounts in pregnancy.

During breastfeeding, horseradish at food amounts is likely safe, but goldenseal, stinging nettle, eyebright, and yarrow all lack sufficient safety data — talk with your doctor or pharmacist before use if you are nursing.

Side effects, ingredient by ingredient Horseradish Goldenseal Stinging Nettle Eyebright Yarrow

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?
  • 5 of the 5 matched ingredients can interact with medications — Eyebright, Yarrow, Horseradish, Stinging Nettle, Goldenseal.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; diabetes medications; heart-rhythm medications; lithium.
  • For scale: 1,255 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 take Pollen Defense, double-check the following medication types with your doctor or pharmacist: blood thinners and antiplatelet drugs (warfarin and aspirin-like medications), diabetes drugs, blood-pressure medications, sedatives (CNS depressants), drugs that depend on liver breakdown via CYP3A4, CYP2D6, or CYP2C9 enzymes, diuretics, lithium, and thyroid hormone replacement. All of these have Moderate interactions documented with one or more ingredients in this product.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFormula with limited ingredient disclosure with insufficient evidence for its stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

Pollen Defense may appeal to someone looking for a traditional herbal approach to respiratory or allergy symptoms, but the evidence for its ingredients is not well established. You should avoid or carefully consider this product if you take blood thinners, diabetes medication, blood-pressure drugs, sedatives, or lithium — all have documented interactions with ingredients here.

If you're pregnant or breastfeeding, talk with your doctor or pharmacist before starting, as several ingredients lack safety data or are rated unsafe. Check your medications with the tool on this page, then discuss the result with your own healthcare provider.

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 Feb 22, 2024.

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 Pollen Defense, straight from the product label.

Brand Herb Pharm
Barcode (UPC) 090900000170
Net contents 1 Fluid Ounce(s); 30 mL
Market status On market
Date entered into DSLD Feb 22, 2024
DSLD ID 307815
Product type Botanical
Supplement form Liquid
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), 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 Pollen Defense by Herb Pharm, 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:
0.7 mL
Maximum serving Sizes:
0.7 mL
Servings per container
42
UPC/BARCODE
090900000170
IngredientAmount% DV
Proprietary Extract Blend662 mg--
Horseradish Root Extract0 NP--
Goldenseal Rhizome with Rootlet Extract0 NP--
Stinging Nettle Seed Extract0 NP--
Eyebright Flowering Aerial Parts Extract0 NP--
Yarrow Flowering Top Extract, Wild0 NP--

Other ingredients: Cane Alcohol, Water, Distilled, Glycerin

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.
Suggested/Recommended/Usage/Directions

Suggested use Shake well before using Adults: Add 1 squeeze of the dropper bulb to 2 oz. of water or juice, 2 to 5 times per day. Best taken between meals.

Precautions

Caution: Seek expert medical advice before taking during pregnancy or nursing.

Keep out of the reach of children

Storage

Store away from heat & light

Formulation

Respiratory System

Gluten-free

FDA Statement of Identity

Herbal Supplement

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.

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

See for yourself

Pollen Defense by Herb Pharm label

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

Pollen Defense 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 Pollen Defense by Herb Pharm

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

Serving size0.7 mL Dosage formLiquid Servings per container42 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: Cane Alcohol, Water, Distilled, Glycerin. These complete the product’s ingredient list but are not active constituents.

Interaction report

Pollen Defense by Herb Pharm Drug Interactions

Want to check YOUR meds against Pollen Defense?

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
1,254Drugs
1,253 Moderate 1 Minor

Ingredients driving the most interactions

Goldenseal Rhizome with Rootlet Extract 1,237
Stinging Nettle Seed Extract 164
Eyebright Flowering Aerial Parts Extract 86
Horseradish Root Extract 16
Yarrow Flowering Top Extract, Wild 1

Individual Drug Interactions

The ingredients in Pollen Defense interact with 1,254 drugs. Click any drug to see the details.

5 of the 5 ingredients in Pollen Defense interact with drugs. Each result below shows which ingredient is responsible. Goldenseal Rhizome with Rootlet Extract Stinging Nettle Seed Extract Eyebright Flowering Aerial Parts Extract Horseradish Root Extract Yarrow Flowering Top Extract, Wild

Each ingredient & the kinds of drugs it affects

For each ingredient in Pollen Defense 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.

Goldenseal Rhizome with Rootlet Extract16 drug types · 1,237 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, goldenseal might increase the risk of bleeding when used with anticoagulant or antiplatelet drugs.
Goldenseal contains berberine. In vitro and animal research shows that berberine can inhibit platelet aggregation. However, this effect has not been reported in humans.

Likelihood Possible Evidence D
Antidiabetes Drugs

Theoretically, goldenseal might increase the risk of hypoglycemia when used with antidiabetes drugs.
Goldenseal contains berberine. Clinical research shows that berberine can lower blood glucose levels. However, this effect has not been reported with goldenseal.

Likelihood Possible Evidence D
Antihypertensive Drugs

Theoretically, goldenseal might increase the risk of hypotension when taken with antihypertensive drugs.
Goldenseal contains berberine. Animal research shows that berberine can have hypotensive effects. Also, an analysis of clinical research shows that taking berberine in combination with amlodipine can lower systolic and diastolic blood pressure when compared with amlodipine alone. However, this effect has not been reported with goldenseal.

Likelihood Possible Evidence D
Cns Depressants

Theoretically, goldenseal might increase the sedative effects of CNS depressants.
Goldenseal contains berberine. Animal research shows that berberine can have sedative effects. However, this effect has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 2C9 (Cyp2C9) Substrates

Theoretically, goldenseal might increase serum levels of drugs metabolized by CYP2C9.
In vitro research shows that goldenseal root extract can modestly inhibit CYP2C9. This effect may be due to its alkaloid constituents, hydrastine and berberine. However, this effect has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 2D6 (Cyp2D6) Substrates

Goldenseal might increase serum levels of drugs metabolized by CYP2D6.
Clinical and in vitro research shows that goldenseal can significantly inhibit CYP2D6 enzymes, potentially increasing levels of drugs metabolized by CYP2D6.

Likelihood Probable Evidence B
Cytochrome P450 2E1 (Cyp2E1) Substrates

Theoretically, goldenseal might increase serum levels of drugs metabolized by CYP2E1.
In vitro research shows that goldenseal root extract can inhibit the activity of CYP2E1. However, this effect has not been reported in humans.

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

Goldenseal might increase serum levels of drugs metabolized by CYP3A4.
Most clinical and in vitro research shows that goldenseal inhibits CYP3A4 enzyme activity and increases serum levels of CYP3A4 substrates, such as midazolam. However, in one small clinical study, goldenseal did not affect the levels of indinavir, a CYP3A4 substrate, in healthy volunteers. This is likely due to the fact that indinavir has a high oral bioavailability, making it an inadequate probe for CYP3A4 interactions and/or that it is primarily metabolized by hepatic CYP3A, while goldenseal has more potential to inhibit intestinal CYP3A enzyme activity. Both goldenseal extract and its isolated constituents berberine and hydrastine inhibit CYP3A, with hydrastine possibly having more inhibitory potential than berberine.

Likelihood Possible Evidence B
Dextromethorphan (Robitussin Dm, Others)

Theoretically, goldenseal might increase serum levels of dextromethorphan.
Goldenseal contains berberine. A small clinical study shows that berberine can inhibit cytochrome P450 2D6 (CYP2D6) activity and reduce the metabolism of dextromethorphan.

Likelihood Possible Evidence D
Digoxin (Lanoxin)

Goldenseal might increase serum levels of digoxin, although this effect is unlikely to be clinically significant.
Clinical research shows that goldenseal modestly increases digoxin peak levels by about 14% in healthy volunteers. However, goldenseal does not seem to affect other pharmacokinetic parameters such as area under the curve (AUC). This suggests that goldenseal does not cause a clinically significant interaction with digoxin. Digoxin is a P-glycoprotein substrate. Some evidence suggests that goldenseal constituents might affect P-glycoprotein; however, it is unclear whether these constituents inhibit or induce P-glycoprotein.

Likelihood Probable Evidence B
Losartan (Cozaar)

Theoretically, goldenseal might decrease the conversion of losartan to its active form.
Goldenseal contains berberine. A small clinical study shows that berberine inhibits cytochrome P450 2C9 (CYP2C9) activity and reduces the metabolism of losartan. However, this effect has not been reported with goldenseal.

Likelihood Possible Evidence D
Metformin (Glucophage)

Theoretically, goldenseal might reduce blood levels of metformin.
In vitro research shows that goldenseal extract decreases the bioavailability of metformin, likely by interfering with transport, intestinal permeability, or other processes involved in metformin absorption. It is unclear which, if any, of metformin's transporters are inhibited by goldenseal. Goldenseal does not appear to alter the clearance or half-life of metformin.

Likelihood Possible Evidence D
P-Glycoprotein Substrates

Theoretically, goldenseal might increase or decrease serum levels of P-glycoprotein (P-gp) substrates.
There is conflicting evidence about the effect of goldenseal on P-gp. In vitro research suggests that berberine, a constituent of goldenseal, modestly inhibits P-gp efflux. Other evidence suggests that berberine induces P-gp. In healthy volunteers, goldenseal modestly increases peak levels of the P-gp substrate digoxin by about 14%. However, it does not seem to affect other pharmacokinetic parameters such as area under the curve (AUC). This suggests that goldenseal is not a potent inhibitor of P-gp-mediated drug efflux. Until more is known, goldenseal should be used cautiously with P-gp substrates.

Likelihood Probable Evidence B
Pentobarbital (Nembutal)

Theoretically, goldenseal might increase the sedative effects of pentobarbital.
Animal research shows that berberine, a constituent of goldenseal, can prolong pentobarbital-induced sleeping time. However, this effect has not been reported with goldenseal.

Likelihood Possible Evidence D
Tacrolimus (Prograf)

Theoretically, goldenseal might increase serum levels of tacrolimus.
Goldenseal contains berberine. In a 16-year-old patient with idiopathic nephrotic syndrome who was being treated with tacrolimus 6.5 mg twice daily, intake of berberine 200 mg three times daily increased the blood concentration of tacrolimus from 8 to 22 ng/mL. Following a reduction of tacrolimus dosing to 3 mg daily, blood levels of tacrolimus decreased to 12 ng/mL.

Likelihood Possible Evidence D
Oseltamivir (Tamiflu)

Theoretically, goldenseal might reduce the therapeutic effects of oseltamivir by decreasing its conversion to its active form.
In vitro evidence suggests that goldenseal reduces the formation of the active compound from the prodrug oseltamivir. The mechanism of action and clinical relevance is unclear.

Likelihood Possible Evidence D
Goldenseal Rhizome with Rootlet Extract full monograph & interactions

Stinging Nettle Seed Extract4 drug types · 164 drugs

Antidiabetes Drugs

Theoretically, stinging nettle might have additive effects with antidiabetes drugs.
Clinical research shows that stinging nettle might decrease blood glucose levels in patients with diabetes.

Likelihood Possible Evidence B
Diuretic Drugs

Theoretically, combining stinging nettle with diuretic drugs may have additive effects.
Animal research suggests that the above ground parts and roots of stinging nettle may have a diuretic effect.

Likelihood Possible Evidence D
Lithium

Theoretically, stinging nettle might reduce excretion and increase levels of lithium.
Animal research suggests that stinging nettle has diuretic and natriuretic properties, which could alter the excretion of lithium. The dose of lithium might need to be decreased.

Likelihood Possible Evidence D
Warfarin (Coumadin)

There is some concern that stinging nettle might decrease the effects of anticoagulant drugs such as warfarin.
Stinging nettle contains a significant amount of vitamin K. When taken in large quantities, this might interfere with the activity of warfarin.

Likelihood Possible Evidence D
Stinging Nettle Seed Extract full monograph & interactions

Eyebright Flowering Aerial Parts Extract1 drug type · 86 drugs

Antidiabetes Drugs

Theoretically, eyebright might increase the risk of hypoglycemia when taken with antidiabetes drugs.
Animal research suggests that eyebright lowers blood glucose levels.

Likelihood Possible Evidence D
Eyebright Flowering Aerial Parts Extract full monograph & interactions

Horseradish Root Extract1 drug type · 16 drugs

Thyroid Hormone

Theoretically, horseradish might interfere with the effects of thyroid hormone.
Horseradish and other members of the cabbage and mustard family are associated with depressed thyroid function.

Likelihood Possible Evidence D
Horseradish Root Extract full monograph & interactions

Yarrow Flowering Top Extract, Wild1 drug type · 1 drug

Lithium

Theoretically, taking yarrow with lithium might increase the levels and adverse effects of lithium.
Animal research shows that yarrow has diuretic activity. Theoretically, due to these potential diuretic effects, yarrow might reduce excretion and increase levels of lithium. The dose of lithium might need to be decreased.

Likelihood Probable Evidence D
Yarrow Flowering Top Extract, Wild full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Pollen Defense, from the product label.

Herb Pharm

See all Herb Pharm products
Name
Herb Pharm
City
Williams
State
OR
ZipCode
97544
Phone Number
800-348-4372
Web Address
www.herb-pharm.com
Pharmacist Counseling Corner

Pollen Defense by Herb Pharm: Common Questions

Does Pollen Defense by Herb Pharm interact with any medications?
Yes. Based on its ingredients, Pollen Defense has a known interaction with 1,254 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Pollen Defense 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 take Pollen Defense if I'm pregnant?
No — goldenseal, stinging nettle, eyebright, and yarrow are all rated likely unsafe in pregnancy. Horseradish should be kept to food amounts only. Talk with your doctor before using any of these if you're pregnant.
Is this safe to use while breastfeeding?
It's not clear. Horseradish at food amounts is likely safe, but goldenseal, stinging nettle, eyebright, and yarrow all lack enough safety data for breastfeeding. Check with your doctor or pharmacist before using this product if you're nursing.
What does horseradish do in this formula?
Horseradish root is traditionally used to support respiratory and urinary tract health, though the evidence for these uses is insufficient. In large amounts, it can irritate your digestive tract and mouth.
I take a blood thinner — is this product okay for me?
No — stinging nettle contains vitamin K, which can interfere with how warfarin works, and goldenseal may increase bleeding risk. Do not take Pollen Defense without checking with your doctor first.
Does this actually work for allergies or colds?
We don't have established evidence that the ingredients in Pollen Defense are effective for allergic rhinitis, common cold, or cough. All are rated insufficient evidence to rate, meaning the science hasn't confirmed they work for these purposes.
What side effects might I notice?
Most commonly, you might experience constipation, diarrhea, nausea, headache, or bitter taste. Large amounts of horseradish or goldenseal can cause gastrointestinal upset and vomiting. Contact with the raw stinging nettle plant causes itching and rash.

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.

Pollen Defense label
Go deeper

The Full Monographs Behind Pollen Defense’s Ingredients

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

Herb & supplement monograph

Horseradish

Interacts with 16 drugs

Horseradish is a pungent root used as a food and folk remedy, most often for sinus congestion and urinary tract complaints. Human evidence is limited, and while culinary amounts are generall...

Read the full Horseradish monograph → Herb & supplement monograph

Goldenseal

Interacts with 1,237 drugs

Goldenseal is a popular North American herb that contains berberine, a compound studied for antimicrobial effects. However, strong human evidence for its many traditional uses is largely lac...

Read the full Goldenseal monograph → Herb & supplement monograph

Stinging Nettle

Interacts with 164 drugs

Stinging nettle is a common plant used as food and in traditional medicine, most often for prostate symptoms, allergies, and joint pain. The evidence is mixed and mostly preliminary, so it i...

Read the full Stinging Nettle monograph → Herb & supplement monograph

Eyebright

Interacts with 86 drugs

Eyebright is a traditional herb long used for minor eye irritation, redness, and allergy symptoms, but high-quality human studies are very limited. There is not enough reliable evidence to c...

Read the full Eyebright monograph → Herb & supplement monograph

Yarrow

Interacts with 1 drug

Yarrow is a traditional herb long used for wounds, digestive complaints, and colds, but high-quality human studies are very limited, so its benefits are not well proven. It is generally used...

Read the full Yarrow monograph →
Sources

Sources & How We Checked

Pollen Defense'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 75 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.

Horseradish 6 references
  1. Blumenthal M, ed. The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. Trans. S. Klein. Boston, MA: American Botanical Council, 1998.
  2. Newall CA, Anderson LA, Philpson JD. Herbal Medicine: A Guide for Healthcare Professionals. London, UK: The Pharmaceutical Press, 1996.
  3. The Review of Natural Products by Facts and Comparisons. St. Louis, MO: Wolters Kluwer Co., 1999.
  4. Electronic Code of Federal Regulations. Title 21. Part 182 -- Substances Generally Recognized As Safe. Available at: https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?CFRPart=182
  5. Panter, K. E. and James, L. F. Natural plant toxicants in milk: a review. J Anim Sci 1990;68(3):892-904. PubMed
  6. Lehmann CU, Puckett AL, Betz BO. 56-year-old man - increased heart rate - weakness - intense sweating - horseradish consumption - Dx?. J Fam Pract 2022;71(7):317-321. PubMed

See these in context on the Horseradish monograph →

Goldenseal 34 references
  1. Chan E. Displacement of bilirubin from albumin by berberine. Biol Neonate 1993;63:201-8. PubMed
  2. Budzinski JW, Foster BC, Vandenhoek S, Arnason JT. An in vitro evaluation of human cytochrome P450 3A4 inhibition by selected commercial herbal extracts and tinctures. Phytomedicine 2000;7:273-82. PubMed
  3. Sandhu RS, Prescilla RP, Simonelli TM, Edwards DJ. Influence of goldenseal root on the pharmacokinetics of indinavir. J Clin Pharmacol 2003;43:1283-8.. PubMed
  4. Janbaz KH, Gilani AH. Studies on preventive and curative effects of berberine on chemical-induced hepatotoxicity in rodents. Fitoterapia 2000;71:25-33.. PubMed
  5. Gurley BJ, Gardner SF, Hubbard MA, et al. In vivo effects of goldenseal, kava kava, black cohosh, and valerian on human cytochrome P450 1A2, 2D6, 2E1, and 3A4/5 phenotypes. Clin Pharmacol Ther 2005;77:415-26. PubMed
  6. Gurley BJ, Swain A, Barone GW, et al. Effect of goldenseal (Hydrastis canadensis) and kava kava (Piper methysticum) supplementation on digoxin pharmacokinetics in humans. Drug Metab Dispos 2007;35:240-5. PubMed
  7. Gurley BJ, Swain A, Hubbard MA, et al. Clinical assessement of CYP2D6-mediated herb-drug interactions in humans: Effects of milk-thistle, black cohosh, goldenseal, kava kava, St. John's wort, and Echinacea. Mol Nutr Food Res 2008;52:755-63.
  8. Zhang Y, Li X, Zou D, et al. Treatment of type 2 diabetes and dyslipidemia with the natural plant alkaloid berberine. J Clin Endocrinol Metab 2008;93:2559-65. PubMed
  9. Chatterjee P, Franklin MR. Human cytochrome p450 inhibition and metabolic-intermediate complex formation by goldenseal extract and its methylenedioxyphenyl components. Drug Metab Dispos 2003;31:1391-7. PubMed
  10. Choudhry, V. P., Sabir, M., and Bhide, V. N. Berberine in giardiasis. Indian Pediatr. 1972;9(3):143-146.
  11. Shanbhag, S. M., Kulkarni, H. J., and Gaitonde, B. B. Pharmacological actions of berberine on the central nervous system. Jpn.J Pharmacol 1970;20(4):482-487. PubMed
  12. Wu, J. F. and Liu, T. P. [Effects of berberine on platelet aggregation and plasma levels of TXB2 and 6-keto-PGF1 alpha in rats with reversible middle cerebral artery occlusion]. Yao Xue.Xue.Bao. 1995;30(2):98-102.
  13. Peng, W. H., Hsieh, M. T., and Wu, C. R. Effect of long-term administration of berberine on scopolamine-induced amnesia in rats. Jpn J Pharmacol 1997;74(3):261-266. DOI
  14. Sharda DC. Berberine in the treatment of diarrhoea of infancy and childhood. J Indian M A 1970;54(1):22-24.
  15. Sabir M and Bhide NK. Study of some pharmacological actions of berberine. Ind J Physiol & Pharmac 1971;15(3):111-132.
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Stinging Nettle 23 references
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Eyebright 4 references
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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.

© 2021 Therapeutic Research Center, LLC

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