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Dietary supplement

Premier Oregano Oil Ingredients & Drug Interactions

by Premier Research Labs

Premier Oregano Oil label
See full label image
Liquid Category: Non-nutrient/non-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 Premier 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

Premier Oregano Oil is a dietary supplement by Premier Research Labs 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 Carvacrol. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Premier Oregano Oil by Premier Research Labs

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

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of Premier Oregano Oil by Premier Research Labs

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

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 1 of its 1 active ingredient.
  • No proprietary blends here — you can verify the dose of every single component.

Premier Oregano Oil is a liquid supplement with one active ingredient: carvacrol, the compound responsible for oregano's therapeutic effects. The supplement is suspended in extra virgin olive oil as an inactive ingredient.

Does it work?

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

The graded evidence we hold for these ingredients covers different conditions than the ones this product is marketed for, so there's no established rating for its stated use — see Oregano's own graded uses on its monograph.

Why this rating?
  • The label markets this product for: Traditional health and wellness support.
  • We looked for evidence on: Acne, Bronchitis, Cough, Dandruff, Dyspepsia, Gingivitis — and 4 related terms.
  • The closest evidence on file: Oregano is rated "Insufficient Reliable Evidence To Rate" for Acne (Natural Medicines).
  • Also on file: Oregano is rated "Insufficient Reliable Evidence To Rate" for Bronchitis, Cough, Dyspepsia, Gingivitis, and more.

The evidence on oregano oil's effectiveness isn't established in the data we hold. Its listing covers acne, bronchitis, asthma, headache, and upper respiratory tract infections—all rated as having insufficient reliable evidence to rate.

That doesn't mean it doesn't work; it means the clinical trials aren't strong enough yet to say one way or the other.

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 is well tolerated at food amounts. Concentrated oregano oil supplements are stronger and less studied than food-level use, so caution is warranted.

The most common side effect from oral use is gastrointestinal upset. Rarely, allergic reactions including anaphylaxis have been reported, and topical application can cause dermatitis in sensitive people, especially at concentrations above 1%.

During pregnancy, medicinal or supplement amounts should be avoided; food amounts are likely fine. While breastfeeding, stick to normal food amounts—the safety of oregano supplements hasn't been 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 product, check with your pharmacist if you take blood thinners or antiplatelet drugs (like warfarin or clopidogrel)—oregano oil may increase bleeding risk. Also double-check if you're on diabetes medications, since 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 glanceFully disclosed formula with no established evidence rating for its marketed use. Moderate medication interactions have been identified, and safety information is well characterized.

Consider this if you're looking for an oregano supplement and don't take blood thinners or diabetes medications. If you do take either of those drug types, talk with your pharmacist before starting.

Oregano oil is generally well tolerated at food levels, but concentrated supplements carry more risk and less research backing them.

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 May 22, 2020.

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 Premier Oregano Oil, straight from the product label.

Brand Premier Research Labs
Net contents 0.5 Fluid Ounce(s); 15 mL
Market status On market
Date entered into DSLD May 22, 2020
DSLD ID 219542
Product type Non-nutrient/non-botanical
Supplement form Liquid
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years)
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 Premier Oregano Oil by Premier Research Labs, 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:
0.09 mL
Maximum serving Sizes:
0.09 mL
Servings per container
166
IngredientAmount% DV
Carvacrol18 mg--

Other ingredients: extra virgin Olive Oil

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: Take 5 drops, twice daily in 2 oz. of water or with food. Feeling a heat sensation after use is normal. Cap tightly to avoid evaporation.

Formula

Features European oil of oregano with naturally occurring carvacrol

European essential oil of oregano

Precautions

Avoid contact with eyes and genital regions.

Tamper Seal: Use only if seal is intact.

If pregnant or nursing, consult a health professional before taking.

Keep out of reach of children.

FDA Disclaimer Statement

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

Formulation

Traditional health and wellness support

FDA Statement of Identity

Dietary Supplement

Storage

Store in a cool, dry place.

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

See for yourself

Premier Oregano Oil by Premier Research Labs label

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

Premier 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 Premier Oregano Oil by Premier Research Labs

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

Serving size0.09 mL Dosage formLiquid Servings per container166 Amounts shown are per serving.

Carvacrol

Interacts with
208 drugs
18 mg per serving Form: Oregano Essential Oil

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

Carvacrol monograph & interactions

Other (inactive) ingredients: Extra virgin Olive Oil. These complete the product’s ingredient list but are not active constituents.

Interaction report

Premier Oregano Oil by Premier Research Labs Drug Interactions

Want to check YOUR meds against Premier 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

Carvacrol 208

Individual Drug Interactions

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

1 of the 1 ingredient in Premier Oregano Oil interact with drugs. Each result below shows which ingredient is responsible. Carvacrol

Each ingredient & the kinds of drugs it affects

For each ingredient in Premier 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.

Carvacrol2 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
Carvacrol full monograph & interactions
The maker

Brand information

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

Premier Research Labs

See all Premier Research Labs products
Name
Premier Research Labs
Pharmacist Counseling Corner

Premier Oregano Oil by Premier Research Labs: Common Questions

Does Premier Oregano Oil by Premier Research Labs interact with any medications?
Yes. Based on its ingredients, Premier 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?
Premier 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.
Can I take this while pregnant?
The safety data advises against medicinal or supplement amounts during pregnancy. Food amounts of oregano are likely fine, but concentrated oregano oil supplements fall into a different category. Talk with your doctor or pharmacist about whether this product is right for you during pregnancy.
Is oregano oil safe while breastfeeding?
There isn't enough data to know either way. The safety of oregano supplements while breastfeeding hasn't been established. Stick to normal food amounts if you're nursing, and talk with your pharmacist for personalized advice about using a supplement.
What's the most common side effect?
Gastrointestinal upset—stomach discomfort or digestive issues—is the most common side effect when oregano oil is taken by mouth. Most people tolerate it well at food-level amounts, but concentrated supplements carry more uncertainty.
What if I have an allergy to oregano or thyme?
Allergic reactions to oregano have been reported, including rare serious ones like anaphylaxis. If you know you're allergic to oregano, thyme, or other plants in the mint family (Lamiaceae), avoid this supplement and talk with your pharmacist.
Does oregano oil actually work for colds or bronchitis?
We don't have enough reliable evidence to say. Upper respiratory infections and bronchitis are listed as uses, but the clinical evidence isn't strong enough yet to rate whether it works for those conditions.

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

Not sure if Premier 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.

Premier Oregano Oil label
Go deeper

The Full Monographs Behind Premier 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

Premier 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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