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

Oregano Oil Ingredients & Drug Interactions

by Protocol For Life Balance

Oregano Oil label
See full label image
Softgel Capsule 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 Protocol For Life Balance with 3 active ingredients. Its ingredients are commonly taken for digestive upset, respiratory and cold symptoms, antimicrobial support.Based on those ingredients, 1,015 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Ginger oil, Fennel oil, 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 Oregano Oil by Protocol For Life Balance

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

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of Oregano Oil by Protocol For Life Balance

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

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 3 of its 3 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

This softgel contains three plant oils: oregano oil, ginger oil, and fennel oil. These are the active ingredients — the parts believed to produce the product's effects.

The other ingredients (gelatin, glycerin, water, enteric coating, carob, and extra virgin olive oil) are inactive and serve to deliver the oils in capsule form and protect them in your stomach. Oregano oil and ginger oil are concentrated extracts of the culinary herbs oregano and ginger, while fennel oil comes from fennel seeds.

All three are widely used in cooking, but the supplement form here is much more potent than what you'd get from seasoning a meal.

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.

Why this rating?
  • The label markets this product for: immune system and free radical support.
  • We looked for evidence on: Upper respiratory tract infection (URTI), Bronchitis, Cough, Immune function, Antioxidant defense, Respiratory health — and 1 related terms.
  • The closest evidence on file: Fennel is rated "Insufficient Reliable Evidence To Rate" for Bronchitis (Natural Medicines).
  • Also on file: Fennel is rated "Insufficient Reliable Evidence To Rate" for Upper respiratory tract infection (URTI), Cough.
  • Also on file: Oregano is rated "Insufficient Reliable Evidence To Rate" for Bronchitis, Upper respiratory tract infection (URTI), Cough.

The evidence for oregano oil's effectiveness is insufficient to rate it reliably for the conditions listed — acne, bronchitis, asthma, headache, and upper respiratory tract infection. Ginger oil has stronger evidence: it's possibly effective for pregnancy-induced nausea and vomiting, and for dysmenorrhea (painful periods), and possibly effective for osteoarthritis, but it's possibly ineffective for exercise-induced muscle soreness and chemotherapy-induced nausea.

Fennel oil is possibly effective for dysmenorrhea, but evidence is insufficient for bronchitis, anxiety, nocturnal enuresis, and cholera. If you're considering this product for a specific condition, check with your doctor about whether the evidence supports its use.

The evidence, ingredient by ingredient Oregano Ginger Fennel

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 3 of the 3 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 3 of 3.
  • General safety write-ups exist for 3 of 3.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Oregano oil is well tolerated in food amounts, but concentrated supplement doses are much stronger and less studied. The most common side effect is gastrointestinal upset; rarely, allergic reactions including anaphylaxis have been reported.

Ginger is generally well tolerated at typical food and supplement doses, though doses above 5 grams per day increase the risk of side effects like heartburn, diarrhea, burping, and burning sensations in the mouth and throat. Fennel seems well tolerated overall, but gastrointestinal discomfort, photosensitivity, and allergic reactions can occur; seizures have been reported rarely.

Regarding pregnancy: oregano oil is possibly unsafe and should be avoided at medicinal doses during pregnancy (food amounts are likely fine). Ginger is likely or possibly safe and is often used for morning sickness, but check with your doctor first and keep amounts moderate.

Fennel is possibly unsafe during pregnancy due to limited safety data and hormone-like effects. For breastfeeding, ginger is likely safe, but oregano and fennel have insufficient safety data — stick to food amounts and talk with your doctor before using supplements.

Side effects, ingredient by ingredient Oregano Ginger Fennel

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?
  • 3 of the 3 matched ingredients can interact with medications — Fennel, Oregano, Ginger.
  • 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: 1,016 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, double-check with your doctor or pharmacist if you take blood thinners (anticoagulants) or antiplatelet drugs like warfarin or aspirin — oregano and ginger may increase bleeding risk. Also watch for diabetes medications, birth control pills, hormone replacement therapy, or medications metabolized by your liver (CYP3A4 substrates and P-glycoprotein substrates), as all three oils interact with one or more of these categories.

If you take ciprofloxacin, nifedipine, losartan, or tamoxifen, these warrant a check as well.

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.

This product combines three herbal oils with a long culinary history, but the supplement doses are much stronger than cooking amounts and come with documented interactions with blood thinners, diabetes drugs, and several other medications. If you take any prescription or over-the-counter medications, especially blood thinners or diabetes drugs, check them against the interaction tool on this page before starting.

Even if you don't find your medication listed, talk with your doctor or pharmacist first — the breadth of interactions means it's worth a quick review of your individual situation.

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

Assessment coverage: 3 of 3 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Jan 22, 2022.

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 Protocol For Life Balance
Barcode (UPC) 707359147324
Net contents 90 Softgel(s)
Market status On market
Date entered into DSLD Jan 22, 2022
DSLD ID 258688
Product type Botanical
Supplement form Softgel Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Women (not pregnant or lactating), Gluten Free, Dairy 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 Oregano Oil by Protocol For Life Balance, 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 Softgel(s)
Maximum serving Sizes:
1 Softgel(s)
Servings per container
90
UPC/BARCODE
707359147324
IngredientAmount% DV
Oregano oil181 mg--
Ginger oil17.6 mg--
Fennel oil19.3 mg--

Other ingredients: Gelatin, Glycerin, Water, Enteric Coating, Carob, 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 usage: Take 1 softgel 1 to 3 times daily with food, or as directed by your healthcare practitioner.

Formulation

How it works: Oregano (Origanum vulgare) is a perennial herb with a long history of traditional use. Oregano oil possesses powerful, free radical-neutralizing compounds, some of which support healthy, normal immune system responses. Modern studies indicate that oregano oil may also help maintain healthy intestinal flora balance. Protocol for Life Balance Oregano Oil Softgels are standardized to ensure a minimum of 55% carvacrol, one of oregano's active constituents, and are enteric coated for release in the small intestine.

- Intestinal support

Not manufactured with yeast, wheat, gluten, soy, milk, egg, fish or shellfish ingredients.

Natural color variation may occur in this product.

Formula

Protocol for Life Balance Oregano Oil Softgels are standardized to ensure a minimum of 55% carvacrol, one of oregano's active constituents, and are enteric coated for release in the small intestine.

With ginger and fennel oils

- Min. 55% Carvacrol

Precautions

Cautions/Interactions: For adults only.

Do not take this product if you are allergic to oregano, fennel or ginger.

Not recommended for pregnant or nursing women. Consult your healthcare practitioner if taking medication or have a medical condition.

Keep out of reach of children.

Not manufactured with yeast, wheat, gluten, soy, milk, egg, fish or shellfish ingredients. Produced in a GMP facility that processes other ingredients containing these allergens.

FDA Statement of Identity

A Dietary Supplement

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.

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

See for yourself

Oregano Oil by Protocol For Life Balance 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 Protocol For Life Balance

These are the 3 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 Softgel(s) Dosage formSoftgel Capsule Servings per container90 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.

Oregano oil

Interacts with
208 drugs
181 mg per serving Form: Carvacrol

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 oil monograph & interactions

Ginger oil

Interacts with
1,007 drugs
17.6 mg per serving

Ginger is a widely used culinary spice with a long history in traditional medicine, and it has the strongest evidence for helping with nausea and vomi...

Ginger oil monograph & interactions

Fennel oil

Interacts with
740 drugs
19.3 mg per serving

Fennel is a Mediterranean herb widely used as a food and spice, and traditionally taken for digestive complaints, colic, and menstrual cramps. Some sm...

Fennel oil monograph & interactions

Other (inactive) ingredients: Gelatin, Glycerin, Water, Enteric Coating, Carob, Extra Virgin Olive Oil. These complete the product’s ingredient list but are not active constituents.

Interaction report

Oregano Oil by Protocol For Life Balance 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
1,015Drugs
882 Moderate 133 Minor

Ingredients driving the most interactions

Ginger oil 1,007
Fennel oil 740
Oregano oil 208

Individual Drug Interactions

The ingredients in Oregano Oil interact with 1,015 drugs. Click any drug to see the details.

3 of the 3 ingredients in Oregano Oil interact with drugs. Each result below shows which ingredient is responsible. Ginger oil Fennel oil Oregano oil

Each ingredient & the kinds of drugs it affects

For each ingredient in Oregano Oil 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.

Ginger oil14 drug types · 1,007 drugs

Anticoagulant/Antiplatelet Drugs

Ginger may have antiplatelet effects and may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs. However, research is conflicting.
Laboratory research suggests that ginger inhibits thromboxane synthetase and decreases platelet aggregation. However, this has not been demonstrated unequivocally in humans, with mixed results from clinical trials. Theoretically, excessive amounts of ginger might increase the risk of bleeding when used with anticoagulant/antiplatelet drugs.

Likelihood Possible Evidence B
Antidiabetes Drugs

Theoretically, taking ginger with antidiabetes drugs might increase the risk of hypoglycemia.
Animal and human research suggests that ginger might increase insulin levels and/or decrease blood glucose levels.

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

Ginger might increase or decrease the levels of CYP3A4 substrates.
In vitro research and some case reports suggest that ginger inhibits CYP3A4 activity. Three case reports from the World Health Organization (WHO) adverse drug reaction database describe increased toxicity in patients taking ginger and cancer medications that are CYP3A4 substrates (imatinib, dabrafenib, and crizotinib). However, the causality of this interaction is unclear due to the presence of multiple interacting drugs and routes of administration.
Conversely, other in vitro research suggests that ginger induces CYP3A4 activity, leading to reduced levels of CYP3A4 substrates. However, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Losartan (Cozaar)

Theoretically, ginger might increase levels of losartan and the risk of hypotension.
In animal research, ginger increased the levels and hypotensive effects of a single dose of losartan. It is not clear if ginger alters the concentration or effects of losartan when taken continuously. Additionally, this interaction has not been shown in humans.

Likelihood Possible Evidence D
Nifedipine (Procardia)

Ginger may have antiplatelet effects and increase the risk of bleeding if used with nifedipine.
Clinical research shows that combined treatment with ginger 1 gram plus nifedipine 10 mg significantly inhibits platelet aggregation when compared to nifedipine or ginger alone.

Likelihood Possible Evidence B
P-Glycoprotein Substrates

Ginger might increase the absorption and blood levels of P-glycoprotein (P-gp) substrates.
In vitro research and case reports suggest that ginger inhibits drug efflux by P-gp, potentially increasing absorption and serum levels of P-gp substrates. Two case reports from the World Health Organization (WHO) adverse drug reaction database describe increased toxicity in patients taking ginger and cancer medications that are P-gp substrates (trametinib, crizotinib). However, the causality of this interaction is unclear due to the presence of multiple interacting drugs and routes of administration.

Likelihood Possible Evidence D
Phenprocoumon (Marcoumar, Others)

Ginger might increase the risk of bleeding with phenprocoumon.
Phenprocoumon, a warfarin-related anticoagulant, might increase the international normalized ratio (INR) when taken with ginger. There is one case report of a 76-year-old woman with a stable INR on phenprocoumon that increased to greater than 10 when she began consuming dried ginger and ginger tea.

Likelihood Possible Evidence D
Warfarin (Coumadin)

Ginger might increase the risk of bleeding with warfarin.
Laboratory research suggests that ginger might inhibit thromboxane synthetase and decrease platelet aggregation. In one case report, ginger increased the INR when taken with phenprocoumon, which has similar pharmacological effects as warfarin. In another case report, ginger increased the INR when taken with a combination of warfarin, hydrochlorothiazide, and acetaminophen. A longitudinal analysis suggests that taking ginger increases the risk of bleeding in patients taking warfarin for at least 4 months. However, research in healthy people suggests that ginger has no effect on INR, or the pharmacokinetics or pharmacodynamics of warfarin. Until more is known, monitor INRs closely in patients taking large amounts of ginger.

Likelihood Possible Evidence B
Calcium Channel Blockers

Theoretically, taking ginger with calcium channel blockers might increase the risk of hypotension.
Some animal and in vitro research suggests that ginger has hypotensive and calcium channel-blocking effects. Another animal study shows that concomitant administration of ginger and the calcium channel blocker amlodipine leads to greater reductions in blood pressure when compared with amlodipine alone.

Likelihood Unlikely Evidence D
Cyclosporine (Neoral, Sandimmune)

Theoretically, when taken prior to cyclosporine, ginger might decrease cyclosporine levels.
In an animal model, ginger juice taken 2 hours prior to cyclosporine administration reduced the maximum concentration and area under the curve of cyclosporine by 51% and 40%, respectively. This effect was not observed when ginger juice and cyclosporine were administered at the same time.

Likelihood Possible Evidence D
Cytochrome P450 1A2 (Cyp1A2) Substrates

Theoretically, ginger might increase the levels of CYP1A2 substrates.
In vitro research shows that ginger inhibits CYP1A2 activity. However, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 2B6 (Cyp2B6) Substrates

Theoretically, ginger might increase the levels of CYP2B6 substrates.
In vitro research shows that ginger inhibits CYP2B6 activity. However, this interaction has not been reported in humans.

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

Theoretically, ginger might increase the levels of CYP2C9 substrates.
In vitro research shows that ginger inhibits CYP2C9 activity. However, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Metronidazole (Flagyl)

Theoretically, ginger might increase levels of metronidazole.
In an animal model, ginger increased the absorption and plasma half-life of metronidazole. In addition, the elimination rate and clearance of metronidazole was significantly reduced.

Likelihood Possible Evidence D
Ginger oil full monograph & interactions

Fennel oil6 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 oil 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
The maker

Brand information

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

Protocol For Life Balance

See all Protocol For Life Balance products
Name
Protocol For Life Balance
Street Address
395 S. Glen Ellyn Rd.
City
Bloomingdale
State
IL
ZipCode
60108
Web Address
www.protocolforlife.com
Pharmacist Counseling Corner

Oregano Oil by Protocol For Life Balance: Common Questions

Does Oregano Oil by Protocol For Life Balance interact with any medications?
Yes. Based on its ingredients, Oregano Oil has a known interaction with 1,015 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 3 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 this if I'm pregnant?
Oregano oil is possibly unsafe at medicinal doses during pregnancy, and fennel is also possibly unsafe due to limited safety data and hormone-like effects. Ginger is often used for morning sickness and is likely or possibly safe, but you should check with your doctor first and keep amounts moderate. Food amounts of all three are likely fine, but this supplement is much more concentrated — talk with your doctor or pharmacist before taking it while pregnant.
Is this product well tolerated, or does it cause side effects?
In food amounts, all three oils are generally well tolerated. At supplement doses, the most common side effect is gastrointestinal upset — heartburn, diarrhea, burping, or discomfort. Ginger doses above 5 grams per day increase side effects. Allergic reactions to any of the three are possible, especially in sensitive individuals; oregano and fennel can cause allergic contact dermatitis, and rare cases of anaphylaxis have been reported with oregano.
Does oregano oil really work for acne, colds, or asthma?
The evidence isn't strong enough to say. For acne, bronchitis, asthma, headaches, and upper respiratory infections, we don't have reliable evidence that oregano oil is effective. Ginger is better studied — it's possibly effective for nausea in pregnancy and painful periods, and possibly effective for osteoarthritis — while fennel is possibly effective for painful periods but hasn't been well tested for other uses listed here.
What's the difference between ginger oil and regular ginger powder?
Ginger oil is a concentrated extract that's much more potent than ginger powder. It comes with the same potential side effects but in a stronger form — that's why higher doses increase the risk of digestive upset and other reactions. The oil form may also be easier on the stomach than powdered ginger for some people, since the encapsulation protects your mouth and throat from the peppery irritant effect.
Can I take this with my blood thinner or diabetes medication?
Both oregano and ginger may increase bleeding risk with blood thinners like warfarin, and all three ingredients may increase low blood sugar (hypoglycemia) risk with diabetes drugs. Use the interaction checker on this page to look up your specific medications, and talk with your doctor or pharmacist before starting — they can advise whether it's safe for you.
What are the inactive ingredients for, and are any of them allergens?
The inactive ingredients — gelatin, glycerin, water, enteric coating, carob, and extra virgin olive oil — are there to make the capsule, protect it in your stomach, and help you swallow it. Gelatin is animal-derived, so it's not suitable for vegetarians or vegans. If you have sensitivities to any of these, let your pharmacist know before taking it.

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 → Herb & supplement monograph

Ginger

Interacts with 1,007 drugs

Ginger is a widely used culinary spice with a long history in traditional medicine, and it has the strongest evidence for helping with nausea and vomiting, including from motion sickness, pr...

Read the full Ginger monograph → 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 →
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 93 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 →

Ginger 64 references
  1. Fischer-Rasmussen W, Kjaer SK, Dahl C, Asping U. Ginger treatment of hyperemesis gravidarum. Eur J Obstet Gynecol Reprod Biol 1991;38:19-24. PubMed
  2. Jewell D, Young G. Interventions for nausea and vomiting in early pregnancy. Cochrane Database Syst Rev 2000;(2):CD000145. PubMed
  3. Vutyavanich T, Kraisarin T, Ruangsri R. Ginger for nausea and vomiting in pregnancy: randomized, double-masked, placebo-controlled trial. Obstet Gynecol 2001;97:577-82. DOI
  4. Backon J. Ginger in preventing nausea and vomiting of pregnancy; a caveat due to its thromboxane synthetase activity and effect on testosterone binding. Eur J Obstet Gynecol Reprod Biol 1991;42:163-4. PubMed
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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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