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Dietary supplement

Oregano Oil Ingredients & Drug Interactions

by Pure Herbs

Oregano Oil 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 Oregano Oil 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

Oregano Oil is a dietary supplement by Pure Herbs with 1 active ingredient. Its ingredients are commonly taken for digestive upset, respiratory and cold symptoms, antimicrobial support.Based on those ingredients, 208 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Oregano Aerial Part Oil, Fresh. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Oregano Oil by Pure Herbs

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

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HelloPharmacist Scorecard of Oregano Oil by Pure Herbs

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 Aug 27, 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 1 active ingredient.

This product contains one active ingredient: oregano oil made from the fresh aerial parts (leaves and stems) of the oregano plant. That's it — no other actives.

The oil is delivered in liquid form, with no inactive fillers or excipients listed.

Does it work?

Couldn't assess
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed
Not assessable

We hold no graded evidence for this product's ingredients for its stated purpose.

Why this rating?
  • The label markets this product for: supporting immune system.
  • Our graded evidence for these ingredients doesn't cover that particular purpose.

The evidence we hold for oregano oil isn't sufficient to rate it for any condition. The product facts list acne, bronchitis, asthma, headache, and upper respiratory tract infection, but for each one the rating is the same: insufficient reliable evidence.

That doesn't mean it doesn't work — it means the research available isn't strong enough yet to say either way.

The evidence, ingredient by ingredient Oregano

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 1 of the 1 matched ingredient.
  • Pregnancy & breastfeeding safety ratings cover 1 of 1.
  • General safety write-ups exist for 1 of 1.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Oregano used as a food seasoning is generally well tolerated. As a concentrated supplement, it's stronger and less studied, so caution is warranted.

The most common side effect when taken by mouth is gastrointestinal upset. Topically, oregano oil can cause skin irritation or allergic dermatitis in sensitive people, especially at concentrations above 1%.

Rare but serious allergic reactions — including anaphylaxis — have been reported. Avoid medicinal or supplement amounts during pregnancy; normal food amounts are likely fine.

While breastfeeding, stick to food amounts, since the safety of oregano supplements isn't established.

Side effects, ingredient by ingredient Oregano

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?
  • 1 of the 1 matched ingredient can interact with medications — Oregano.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; diabetes medications.
  • For scale: 208 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 this oregano oil, double-check with your doctor or pharmacist if you're on blood thinners or antiplatelet drugs — oregano may increase bleeding risk. Also check if you take diabetes medications — oregano might lower blood sugar too much.

These are Moderate-severity interactions.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFormula with limited ingredient disclosure with no assessable stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

Oregano oil is a single-ingredient supplement that may interest people looking for traditional or herbal support, but the evidence for its effectiveness isn't solid yet. If you take blood thinners, antiplatelet drugs, or diabetes medications, you need to check with your doctor or pharmacist before using it.

Talk it over with your own healthcare provider to decide if it's right for you.

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

Assessment coverage: 1 of 1 active ingredient matched to our full ingredient reviews (monographs). Based on the product label dated Jan 23, 2023.

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 Oregano Oil, straight from the product label.

Brand Pure Herbs
Net contents 4 Fluid Ounce(s); 120 mL
Market status On market
Date entered into DSLD Jan 23, 2023
DSLD ID 281408
Product type Botanical
Supplement form Liquid
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Women (not pregnant or lactating)
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 Oregano Oil by Pure Herbs, 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 Drop(s)
Maximum serving Sizes:
1 Drop(s)
Servings per container
5000
IngredientAmount% DV
Oregano Aerial Part Oil, Fresh0 NP--

Other ingredients: None

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

Directions: For adults, mix 1 drop of oil in 2 fl. oz (60 mL) water one time daily preferably with a meal.

Shake well before use

Formulation

Beneficial for supporting immune system.

FDA Disclaimer Statement

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

Precautions

Caution: Dilute before use. May cause skin irritation.

Warning: Not intended for use by pregnant or nursing women. If you have a medical condition or are taking medication, consult your doctor prior to use.

Discontinue use and consult with your doctor if any adverse reactions occur.

Keep out of reach of children

Brand IP Statement(s)

Pure Herbs, Ltd. Natural Herbal Extracts

FDA Statement of Identity

Dietary Supplement

General Statements

"No expense has been spared to provide the finest nature has to offer."

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

See for yourself

Oregano Oil by Pure Herbs label

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

Oregano Oil 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 Oregano Oil by Pure Herbs

This is the 1 active ingredient this product is made of. Select it to open its full monograph.

Serving size1 Drop(s) Dosage formLiquid Servings per container5000 Amounts shown are per serving.

Oregano Aerial Part Oil, Fresh

Interacts with
208 drugs
0 NP per serving

Oregano is a common Mediterranean cooking herb that is also sold as a concentrated oil or supplement, often standardized for a compound called carvacr...

Oregano Aerial Part Oil, Fresh monograph & interactions

Other (inactive) ingredients: None. These complete the product’s ingredient list but are not active constituents.

Interaction report

Oregano Oil by Pure Herbs Drug Interactions

Want to check YOUR meds against Oregano Oil?

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
208Drugs
208 Moderate

Ingredients driving the most interactions

Oregano Aerial Part Oil, Fresh 208

Individual Drug Interactions

The ingredients in Oregano Oil interact with 208 drugs. Click any drug to see the details.

1 of the 1 ingredient in Oregano Oil interact with drugs. Each result below shows which ingredient is responsible. Oregano Aerial Part Oil, Fresh

Each ingredient & the kinds of drugs it affects

For each ingredient in Oregano Oil with known interactions, here are the types of medications it can affect. Open any type for the detail — or search your exact drug in the checker above.

Oregano Aerial Part Oil, Fresh2 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 Aerial Part Oil, Fresh full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Oregano Oil, from the product label.

Pure Herbs

See all Pure Herbs products
Name
Pure Herbs, Ltd.
City
Sterling Heights
State
MI
Phone Number
(800) 860-4372
Web Address
www.pureherbs.com
Pharmacist Counseling Corner

Oregano Oil by Pure Herbs: Common Questions

Does Oregano Oil by Pure Herbs interact with any medications?
Yes. Based on its ingredients, Oregano Oil has a known interaction with 208 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Oregano Oil contains a single active ingredient, and that one ingredient can interact with many different medications on its own. We check it against each medication and show the mechanism responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Is oregano oil safe to use while I'm pregnant?
Oregano as a food seasoning is fine, but medicinal or supplement amounts are possibly unsafe during pregnancy. If you're pregnant or planning to become pregnant, talk with your doctor or pharmacist before taking this supplement.
Can I use oregano oil while breastfeeding?
Normal food amounts of oregano are okay, but the safety of oregano supplements while breastfeeding isn't established. Stick to food amounts, and check with your doctor or pharmacist if you want to use a supplement.
What are the common side effects?
The most common side effect is gastrointestinal upset when taken by mouth. If you apply it topically, it can cause skin irritation or allergic dermatitis in sensitive people. Rare but serious allergic reactions, including anaphylaxis, have been reported.
Does oregano oil actually work for colds or bronchitis?
We don't have enough reliable evidence to say whether it works for upper respiratory infections, bronchitis, or the other conditions listed. The research just isn't solid enough yet to make that call.
Why is this oil stronger than oregano seasoning?
This is a concentrated supplement — much more potent than the dried herb you'd sprinkle on pizza. That's why it's less studied and why we need more caution with it than we do with food amounts.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

Not sure if Oregano Oil is safe with your meds?

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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.

Oregano Oil label
Go deeper

The Full Monographs Behind Oregano Oil’s Ingredients

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

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 →
Sources

Sources & How We Checked

Oregano Oil'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 12 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.

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 →

Parts of this content are provided by the Therapeutic Research Center, LLC.

DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

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