Interactions on record — worth a quick check against your medications. Based on 8 of 9 ingredients. Check your meds →
Dietary supplement

Yeast Buster Ingredients & Drug Interactions

by Village Vitality

Yeast Buster 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 Yeast Buster 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

Yeast Buster is a dietary supplement by Village Vitality with 9 active ingredients. Its ingredients are commonly taken for digestive upset and bloating, infant colic, menstrual cramps.Based on those ingredients, 1,226 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Oregon Grape, Fennel, Oregano Oil. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Yeast Buster by Village Vitality

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

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of Yeast Buster by Village Vitality

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 9 active ingredients.
  • “Proprietary Blend” is a proprietary blend — the label gives one combined amount (460 mg) without saying how much of each component you get.

Yeast Buster is a liquid supplement containing nine active ingredients: fennel, oregano oil, Oregon grape, gentian, fresh spilanthes, pau d'arco, usnea lichen, tea tree oil, and black walnut. These are mixed in a proprietary blend.

The product also contains inactive ingredients—grain alcohol and deionized water—which serve as the liquid base.

Does it work?

Moderate 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
Moderate

Some clinical evidence supports this product's ingredients for its stated purpose, but it isn't conclusive.

Why this rating?
  • The label markets this product for: Yeast and fungal infection support.
  • We looked for evidence on: Onychomycosis, Tinea pedis, Tinea corporis, Tinea capitis, Oropharyngeal candidiasis, Otitis externa — and 3 related terms.
  • The strongest evidence on file: Tea Tree Oil is rated "Possibly Effective" for Onychomycosis (Natural Medicines).
  • Also on file: Tea Tree Oil is rated "Possibly Effective" for Tinea pedis.
  • Also on file: Tea Tree Oil is rated "Insufficient Reliable Evidence To Rate" for Oropharyngeal candidiasis, Tinea corporis, Otitis externa.

The evidence for Yeast Buster's ingredients is limited. Fennel is possibly effective for menstrual cramps (dysmenorrhea), but evidence is insufficient for bronchitis and anxiety.

Oregon grape is possibly effective for psoriasis but lacks reliable evidence for eczema, GERD, and ulcers. Tea tree oil is possibly effective for acne and fungal foot infections (tinea pedis) and possibly for nail fungus (onychomycosis), but evidence is insufficient for bacterial vaginosis and seborrheic dermatitis.

Oregano oil, gentian, pau d'arco, usnea lichen, and black walnut all lack sufficient evidence to rate their effectiveness for the conditions studied. If you're considering this product for a specific condition, ask your pharmacist whether the evidence supports it.

The evidence, ingredient by ingredient Fennel Oregano Oregon Grape Gentian Pau D'arco Usnea Tea Tree Oil Black Walnut

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 8 of the 8 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 8 of 8.
  • General safety write-ups exist for 8 of 8.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Most of Yeast Buster's ingredients are generally well tolerated at typical doses, though some carry cautions. Fennel and oregano oil can cause gastrointestinal upset, allergic reactions, and (rarely) bronchial asthma or seizures — fennel-sensitive people may experience photosensitivity.

Oregon grape, pau d'arco, and usnea lichen are not well studied at high doses; usnea's active compound usnic acid has been linked to liver damage when taken by mouth. Tea tree oil is toxic if swallowed and should never be ingested — it's safe only when diluted on skin.

Black walnut leaves, bark, and hull contain tannins that may cause stomach upset. Allergic reactions, including anaphylaxis, have been reported with oregano in sensitive individuals.

Side effects, ingredient by ingredient Fennel Oregano Oregon Grape Gentian Pau D'arco Usnea Tea Tree Oil Black Walnut

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 8 matched ingredients can interact with medications — Fennel, Oregon Grape, Oregano, Pau D'arco, Gentian.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; diabetes medications.
  • For scale: 1,227 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 taking Yeast Buster, check your medications against these drug types: blood thinners (anticoagulants and antiplatelet drugs), liver-metabolized medications (especially CYP3A4 substrates), blood pressure medications, diabetes medications, and birth control pills. These are the main moderate-severity interactions documented for fennel, Oregon grape, oregano oil, gentian, and pau d'arco 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 some supporting evidence for its stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

Talk to your pharmacist before using Yeast Buster if you take blood thinners, blood pressure medications, diabetes drugs, or liver-metabolized prescriptions — this product has multiple documented interactions. Avoid it during pregnancy and breastfeeding; several ingredients carry safety cautions for both.

It's generally well tolerated for short-term use in adults without these conditions, but evidence of effectiveness is limited for most uses.

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

Assessment coverage: 8 of 9 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated May 23, 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 Yeast Buster, straight from the product label.

Brand Village Vitality
Barcode (UPC) 788332165016
Net contents 1 Fluid Ounce(s); 30 Milliliter(s)
Market status On market
Date entered into DSLD May 23, 2024
DSLD ID 310352
Product type Botanical
Supplement form Liquid
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Organic
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 Yeast Buster by Village Vitality, 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:
1 mL
Servings per container
30
UPC/BARCODE
788332165016
IngredientAmount% DV
Proprietary Blend460 mg--
Fennel0 NP--
Oregano Oil0 NP--
Oregon Grape0 NP--
Gentian0 NP--
fresh Spilanthes0 NP--
Pau d'Arco0 NP--
Usnea Lichen0 NP--
Tea Tree Oil0 NP--
Black Walnut, Fresh0 NP--

Other ingredients: Grain Alcohol, Water, Deionized

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

Suggest use: Take 30 drops 3 times per day in water before meals.

Shake well before using.

Precautions

Warnings: Keep out of the reach of children.

FDA Disclaimer Statement

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

FDA Statement of Identity

Herbal Supplement

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

See for yourself

Yeast Buster by Village Vitality label

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

Yeast Buster 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 Yeast Buster by Village Vitality

These are the 9 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 mL Dosage formLiquid Servings per container30 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.

Proprietary Blend

460 mg per serving

Other (inactive) ingredients: Grain Alcohol, Water, Deionized. These complete the product’s ingredient list but are not active constituents.

Interaction report

Yeast Buster by Village Vitality Drug Interactions

Want to check YOUR meds against Yeast Buster?

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
1,226Drugs
1,226 Moderate

Ingredients driving the most interactions

Oregon Grape 1,218
Fennel 740
Oregano Oil 208
Gentian 172
Pau d'Arco 122

Individual Drug Interactions

The ingredients in Yeast Buster interact with 1,226 drugs. Click any drug to see the details.

5 of the 9 ingredients in Yeast Buster interact with drugs. Each result below shows which ingredient is responsible. Oregon Grape Fennel Oregano Oil Gentian Pau d'Arco

Each ingredient & the kinds of drugs it affects

For each ingredient in Yeast Buster 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.

Oregon Grape9 drug types · 1,218 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, Oregon grape might increase the risk of bleeding when taken with anticoagulant or antiplatelet drugs.
In vitro and in vivo research suggests that berberine, a constituent of Oregon grape, can inhibit platelet aggregation.

Likelihood Possible Evidence D
Antidiabetes Drugs

Theoretically, Oregon grape might increase the risk of hypoglycemia when taken with antidiabetes drugs.
Clinical research suggests that berberine, a constituent of Oregon grape, can lower blood glucose levels.

Likelihood Possible Evidence A
Antihypertensive Drugs

Theoretically, Oregon grape might increase the risk of hypotension when taken with antihypertensive drugs.
Animal research suggests that berberine, a constituent of Oregon grape, can have hypotensive effects. Also, an analysis of clinical evidence suggests that taking berberine in combination with amlodipine (Norvasc) can lower systolic and diastolic blood pressure when compared with taking amlodipine alone.

Likelihood Possible Evidence D
Cns Depressants

Theoretically, Oregon grape might increase the sedative effects of CNS depressants.
Animal research suggests that berberine, a constituent of Oregon grape, can have sedative effects.

Likelihood Possible Evidence D
Cyclosporine (Neoral, Sandimmune)

Theoretically, Oregon grape might increase the effects and adverse effects of cyclosporine.
Berberine, a constituent of Oregon grape, can reduce metabolism of cyclosporine and increase serum levels. It might inhibit cytochrome P450 3A4 (CYP3A4), which metabolizes cyclosporine.

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

Theoretically, Oregon grape might increase serum levels of drugs metabolized by CYP2C9.
Preliminary clinical evidence suggests that berberine, a constituent of Oregon grape, can inhibit cytochrome P450 2C9 (CYP2C9).

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

Theoretically, Oregon grape might increase serum levels of drugs metabolized by CYP2D6.
In vitro research and preliminary clinical evidence suggest that berberine, a constituent of Oregon grape, can inhibit cytochrome P450 2D6 (CYP2D6).

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

Theoretically, Oregon grape might increase serum levels of drugs metabolized by CYP3A4.
In vitro research and preliminary clinical evidence suggest that berberine, a constituent of Oregon grape, moderately inhibits cytochrome P450 3A4 (CYP3A4).

Likelihood Possible Evidence D
P-Glycoprotein Substrates

Theoretically, Oregon grape might increase serum levels of drugs that are P-glycoprotein (P-gp) substrates.
In vitro research suggests that Oregon grape extracts inhibit P-gp efflux.

Likelihood Possible Evidence D
Oregon Grape full monograph & interactions

Fennel6 drug types · 740 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, fennel might increase the risk of bleeding when used with antiplatelet or anticoagulant drugs.

Animal research suggests that fennel oil has antithrombotic and antiplatelet effects.

Likelihood Possible Evidence D
Ciprofloxacin (Cipro)

Theoretically, fennel might decrease the levels and clinical effects of ciprofloxacin.

Animal research shows that fennel reduces ciprofloxacin bioavailability by nearly 50%, possibly due to the metal cations such as calcium, iron, and magnesium contained in fennel. This study also found that fennel increased tissue distribution and slowed elimination of ciprofloxacin.

Likelihood Probable Evidence D
Contraceptive Drugs

Theoretically, taking large amounts of fennel might decrease the effects of contraceptive drugs due to competition for estrogen receptors.

Some constituents of fennel have estrogenic activity.

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

Theoretically, fennel might increase levels of drugs metabolized by CYP3A4.

In vitro research suggests that fennel inhibits CYP3A4 enzyme activity. This effect has not been reported in humans.

Likelihood Possible Evidence D
Estrogens

Theoretically, taking large amounts of fennel might interfere with hormone replacement therapy due to competition for estrogen receptors.

Some constituents of fennel have estrogenic activity.

Likelihood Possible Evidence D
Tamoxifen (Nolvadex)

Theoretically, taking large amounts of fennel might decrease the antiestrogenic effect of tamoxifen.

Some constituents of fennel have estrogenic activity, which may interfere with the antiestrogenic activity of tamoxifen.

Likelihood Possible Evidence D
Fennel full monograph & interactions

Oregano Oil2 drug types · 208 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, oregano might increase the risk of bleeding when taken with anticoagulant or antiplatelet drugs.
In vitro research shows that aristolochic acid isolated from oregano leaves has antithrombin activity. It has also been reported that oregano oil inhibits arachidonic acid-induced, and ADP-induced, platelet aggregation.

Likelihood Possible Evidence D
Antidiabetes Drugs

Theoretically, oregano might increase the risk for hypoglycemia when taken with antidiabetes drugs.
In vitro and animal research shows that oregano extracts might lower blood glucose levels.

Likelihood Possible Evidence D
Oregano Oil full monograph & interactions

Gentian1 drug type · 172 drugs

Antihypertensive Drugs

Theoretically, taking gentian with antihypertensive drugs might increase the risk of hypotension.
In vitro research shows that gentian can cause vasodilation and lower blood pressure.

Likelihood Possible Evidence D
Gentian full monograph & interactions

Pau d'Arco1 drug type · 122 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, pau d'arco might increase the risk of bleeding when taken with anticoagulant or antiplatelet drugs.
In vitro research shows that pau d'arco reduces platelet aggregation and may interfere with vitamin K. One clinical study shows that taking the lapachol constituent of pau d'arco in doses above 1.5 grams daily increases the risk of bleeding. The effects of whole pau d'arco or pau d'arco extract in humans are unclear.

Likelihood Possible Evidence D
Pau d'Arco full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Yeast Buster, from the product label.

Village Vitality

See all Village Vitality products
Name
Village Vitality LLC
Street Address
79 Tinker St, Floor 2
City
Woodstock
State
NY
ZipCode
12498
Pharmacist Counseling Corner

Yeast Buster by Village Vitality: Common Questions

Does Yeast Buster by Village Vitality interact with any medications?
Yes. Based on its ingredients, Yeast Buster has a known interaction with 1,226 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Yeast Buster contains 9 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 Yeast Buster while pregnant or breastfeeding?
No — several ingredients carry safety cautions. Fennel, oregano oil, pau d'arco, and gentian are not recommended during pregnancy, and Oregon grape is considered likely unsafe. During breastfeeding, fennel, oregano oil, pau d'arco, and gentian also lack sufficient safety data. Talk to your doctor or midwife before use.
What's in this product supposed to do?
Yeast Buster is formulated with traditional anti-yeast and anti-inflammatory herbs. However, the evidence that these ingredients effectively treat yeast infections or related conditions is limited or not yet established in our data. If you're treating an infection, see your doctor for a proper diagnosis and proven treatment options.
I'm allergic to tree nuts. Is black walnut safe for me?
Black walnut is a tree nut and classified as a major food allergen in the United States. If you have a tree nut allergy, avoid Yeast Buster or check with your allergist first, as cross-reactivity is possible.
Are there any serious side effects I should know about?
Serious side effects are rare but reported: fennel can rarely cause seizures, oregano can cause anaphylaxis in sensitive people, and usnea's usnic acid has been linked to liver damage. Most commonly, users report mild stomach upset, allergic reactions, or skin irritation. Stop use and contact your pharmacist or doctor if you experience unusual symptoms.
Is tea tree oil in Yeast Buster safe to swallow?
No — tea tree oil is toxic if ingested, even in small amounts like 2.5 mL. This product is a liquid, so be careful not to swallow it. If it's meant to be ingested, confirm the safe dose and method with your pharmacist before use. If swallowed accidentally, contact poison control or seek medical help.
What's the difference between this and other yeast supplements?
The evidence we hold doesn't establish how this product compares to others. Each has its own ingredient mix and interaction profile. Your pharmacist can help you weigh options based on your medications and health history.

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.

Yeast Buster label
Go deeper

The Full Monographs Behind Yeast Buster’s Ingredients

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

Herb & supplement monograph

Fennel

Interacts with 740 drugs

Fennel is a Mediterranean herb widely used as a food and spice, and traditionally taken for digestive complaints, colic, and menstrual cramps. Some small studies suggest possible benefit for...

Read the full Fennel monograph → Herb & supplement monograph

Oregano

Interacts with 208 drugs

Oregano is a common Mediterranean cooking herb that is also sold as a concentrated oil or supplement, often standardized for a compound called carvacrol. While lab studies suggest it may hav...

Read the full Oregano monograph → Herb & supplement monograph

Oregon Grape

Interacts with 1,218 drugs

Oregon grape is a shrub whose root contains berberine and related compounds. The strongest (though still modest) evidence is for topical creams that may slightly ease psoriasis; evidence for...

Read the full Oregon Grape monograph → Herb & supplement monograph

Gentian

Interacts with 172 drugs

Gentian is a very bitter root traditionally used to stimulate appetite and ease mild digestive complaints, often as part of "bitters" before meals. The evidence is mostly traditional and pre...

Read the full Gentian monograph → Herb & supplement monograph

Pau D'arco

Interacts with 122 drugs

Pau d'arco is a South American tree bark traditionally used for infections and inflammation, and it contains compounds like lapachol that show activity in lab studies. However, strong human...

Read the full Pau D'arco monograph → Herb & supplement monograph

Usnea

Usnea is a lichen used in traditional herbal medicine, mainly for sore throats, skin infections, and as a general antimicrobial. Laboratory studies suggest its main compound, usnic acid, can...

Read the full Usnea monograph → Herb & supplement monograph

Tea Tree Oil

Tea tree oil is an essential oil used on the skin for acne, fungal infections, and other skin problems, with some supportive but limited evidence. It is for topical use only and should never...

Read the full Tea Tree Oil monograph → Herb & supplement monograph

Black Walnut

Black walnut is a tree whose green hulls are traditionally used as a natural antiparasitic and digestive remedy, but solid human evidence for these uses is lacking. It contains a compound ca...

Read the full Black Walnut monograph →
Sources

Sources & How We Checked

Yeast Buster'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 105 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.

Fennel 17 references
  1. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
  2. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
  3. Zhu M, Wong PY, Li RC. Effect of oral administration of fennel (Foeniculum vulgare) on ciprofloxacin absorption and disposition in the rat. J Pharm Pharmacol 1999;51:1391-6.
  4. Gral N, Beani JC, Bonnot D, et al. [Plasma levels of psoralens after celery ingestion]. Ann Dermatol Venereol 1993;120:599-603.
  5. Burkhard PR, Burkhardt K, Haenggeli CA, Landis T. Plant-induced seizures: reappearance of an old problem. J Neurol 1999;246:667-70. PubMed
  6. Rosti L, Nardini A, Bettinelli ME, Rosti D. Toxic effects of a herbal tea mixture in two newborns. Acta Paediatrica 1994;83:683. PubMed
  7. Cuzzolin L, Zaffani S, and Benoni G. Safety implications regarding use of phytomedicines. Eur.J Clin Pharmacol. 2006;62:37-42. PubMed
  8. Tognolini, M., Ballabeni, V., Bertoni, S., Bruni, R., Impicciatore, M., and Barocelli, E. Protective effect of Foeniculum vulgare essential oil and anethole in an experimental model of thrombosis. Pharmacol.Res 2007;56(3):254-260. PubMed
  9. Subehan, Usia, T., Iwata, H., Kadota, S., and Tezuka, Y. Mechanism-based inhibition of CYP3A4 and CYP2D6 by Indonesian medicinal plants. J Ethnopharmacol. 5-24-2006;105(3):449-455. PubMed
  10. Tognolini, M., Barocelli, E., Ballabeni, V., Bruni, R., Bianchi, A., Chiavarini, M., and Impicciatore, M. Comparative screening of plant essential oils: phenylpropanoid moiety as basic core for antiplatelet activity. Life Sci. 2-23-2006;78(13):1419-1432. PubMed
  11. Subehan, Zaidi, S. F., Kadota, S., and Tezuka, Y. Inhibition on human liver cytochrome P450 3A4 by constituents of fennel (Foeniculum vulgare): identification and characterization of a mechanism-based inactivator. J Agric.Food Chem. 12-12-2007;55(25):101 PubMed
  12. LEVY, S. B. Bronchial asthma due to ingestion of fennel and fennel seed. Ann.Allergy 1948;6(4):415.
  13. Ottolenghi, A., De Chiara, A., Arrigoni, S., Terracciano, L., and De Amici, M. [Diagnosis of food allergy caused by fruit and vegetables in children with atopic dermatitis]. Pediatr Med Chir 1995;17(6):525-530.
  14. Trabace L, Tucci P, Ciuffreda L, et al. "Natural" relief of pregnancy-related symptoms and neonatal outcomes: above all do no harm. J Ethnopharmacol. 2015;174:396-402. PubMed
  15. Denaxa D, Arkwright PD. Fennel as a cause of immediate hypersensitivity to toothpaste. Ann Allergy Asthma Immunol. 2020;125(1):99-100. PubMed
  16. Lee HW, Ang L, Lee MS, Alimoradi Z, Kim E. Fennel for reducing pain in primary dysmenorrhea: a systematic review and meta-analysis of randomized controlled trials. Nutrients 2020;12(11):3438. PubMed
  17. Mathew T, John SK, Javali M, Vasireddy M, Nadig R, Sarma GRK. Substance use related cluster headache: A case series. Headache 2022;62(7):908-910. PubMed

See these in context on the Fennel monograph →

Oregano 12 references
  1. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
  2. Benito M, Jorro G, Morales C, et al. Labiatae allergy: systemic reactions due to ingestion of oregano and thyme. Ann Allergy Asthma Immunol 1996;76:416-8. PubMed
  3. Chevallier A. Encyclopedia of Herbal Medicine. 2nd ed. New York, NY: DK Publ, Inc., 2000.
  4. Ciganda C, and Laborde A. Herbal infusions used for induced abortion. J Toxicol.Clin Toxicol. 2003;41:235-239. PubMed
  5. Futrell, J. M. and Rietschel, R. L. Spice allergy evaluated by results of patch tests. Cutis 1993;52(5):288-290.
  6. Tognolini, M., Barocelli, E., Ballabeni, V., Bruni, R., Bianchi, A., Chiavarini, M., and Impicciatore, M. Comparative screening of plant essential oils: phenylpropanoid moiety as basic core for antiplatelet activity. Life Sci. 2-23-2006;78(13):1419-1432. PubMed
  7. Goun, E., Cunningham, G., Solodnikov, S., Krasnykch, O., and Miles, H. Antithrombin activity of some constituents from Origanum vulgare. Fitoterapia 2002;73(7-8):692-694. PubMed
  8. Lemhadri, A., Zeggwagh, N. A., Maghrani, M., Jouad, H., and Eddouks, M. Anti-hyperglycaemic activity of the aqueous extract of Origanum vulgare growing wild in Tafilalet region. J Ethnopharmacol. 2004;92(2-3):251-256. PubMed
  9. McCue, P., Vattem, D., and Shetty, K. Inhibitory effect of clonal oregano extracts against porcine pancreatic amylase in vitro. Asia Pac.J Clin.Nutr. 2004;13(4):401-408.
  10. Ragi, J., Pappert, A., Rao, B., Havkin-Frenkel, D., and Milgraum, S. Oregano extract ointment for wound healing: a randomized, double-blind, petrolatum-controlled study evaluating efficacy. J.Drugs Dermatol. 2011;10(10):1168-1172.
  11. Singletary K. Oregano: overview of the literature on health benefits. Nutrition Today 2010;45(3):129-38.
  12. Silva MLAE, Lucarini R, Dos Santos FF, et al. Hypoglycemic effect of rosmarinic acid-rich infusion (RosCE) from Origanum vulgare in alloxan-induced diabetic rats. Nat Prod Res 2022;36(17):4525-4531.

See these in context on the Oregano monograph →

Oregon Grape 21 references
  1. Wiesenauer M, Lydtke R. Mahonia aquifolium in patients with Psoriasis vulgaris; an intraindividual study. Phytomedicine 1996;3:231-5.
  2. Chan E. Displacement of bilirubin from albumin by berberine. Biol Neonate 1993;63:201-8. PubMed
  3. Janbaz KH, Gilani AH. Studies on preventive and curative effects of berberine on chemical-induced hepatotoxicity in rodents. Fitoterapia 2000;71:25-33.. PubMed
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Gentian 5 references
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Pau D'arco 6 references
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Usnea 10 references
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Tea Tree Oil 31 references
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See these in context on the Tea Tree Oil monograph →

Black Walnut 3 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. McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
  3. Food and Drug Administration. Food Allergen Labeling and Consumer Protection Act of 2004 (FALCPA); Public Law 108-282, Title II. Accessed on May 19, 2021. Available at: https://www.fda.gov/food/food-allergensgluten-free-guidance-documents-regulatory-infor

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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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