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

Ultracidal Ingredients & Drug Interactions

by Physician's Strength

Ultracidal 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 Ultracidal 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

Ultracidal is a dietary supplement by Physician's Strength with 3 active ingredients. Its ingredients are commonly taken for toothache and oral pain, digestive upset, antimicrobial and antifungal.Based on those ingredients, 1,129 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Clove bud Oil, Cinnamon Bark Oil, Oregano Oil P73, Wild. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Ultracidal by Physician's Strength

Ask about any prescription or over-the-counter medication and we check it for interactions with Ultracidal by Physician's Strength — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Ultracidal by Physician's Strength

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 3 active ingredients.
  • “Proprietary Blend” is a proprietary blend — the label gives one combined amount (240 mg) without saying how much of each component you get.

Ultracidal contains 3 active ingredients: clove bud oil, cinnamon bark oil, and oregano oil (P73, wild). These are concentrated plant extracts—much stronger than the spices you'd use in cooking.

The product has no inactive ingredients listed.

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: healthy immune support.
  • We looked for evidence on: Common cold, Cough, Upper respiratory tract infection (URTI), Bronchitis, Rhinosinusitis, Intestinal parasite infection — and 2 related terms.
  • The closest evidence on file: Clove is rated "Insufficient Reliable Evidence To Rate" for Cough (Natural Medicines).
  • Also on file: Oregano is rated "Insufficient Reliable Evidence To Rate" for Bronchitis, Upper respiratory tract infection (URTI), Cough, Intestinal parasite infection, and more.
  • Also on file: Cassia Cinnamon is rated "Insufficient Reliable Evidence To Rate" for Common cold.

The evidence for what Ultracidal is used for is limited. Clove oil shows possibly effective evidence for ventilator-associated pneumonia (VAP), but insufficient evidence exists for cough, acute pain, and dyspepsia.

Cinnamon bark and oregano oil have insufficient evidence for the conditions they're traditionally used for—diabetes, blood sugar, colds, bronchitis, asthma, respiratory infections, headache, and acne are all unproven in our data. If you're considering this product for a specific health goal, ask your pharmacist what the evidence actually supports.

The evidence, ingredient by ingredient Clove Cassia Cinnamon 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 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.

As a food spice, clove is well tolerated, but concentrated clove oil is toxic in small amounts—just 5 to 10 mL can be dangerous in children. Orally, clove is generally safe at food doses; topical use is well tolerated.

Inhaled clove and intravenous use may be unsafe. Rare serious effects include liver failure from oral exposure.

Cinnamon bark oil is likely safe in food amounts and pregnancy/lactation, but large doses over time carry a risk of liver damage due to its coumarin content. Oregano oil is well tolerated at food amounts but has limited safety data at supplement doses.

Topical oregano oil above 1% concentration may irritate mucous membranes. Rare serious allergic reactions, including anaphylaxis, have been reported.

Stick to normal food amounts unless your provider clears medicinal doses.

Side effects, ingredient by ingredient Clove Cassia Cinnamon 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?
  • 3 of the 3 matched ingredients can interact with medications — Clove, Oregano, Cassia Cinnamon.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; diabetes medications.
  • For scale: 1,130 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 Ultracidal, check your medications against these drug types: antidiabetes drugs (insulin, sulfonylureas, metformin—risk of low blood sugar), blood thinners and antiplatelet drugs like warfarin or aspirin (risk of bleeding), and drugs metabolized by liver CYP450 enzymes (CYP2D6, CYP1A2, CYP3A4, CYP2C9 substrates—possible increase in drug levels). If you take hepatotoxic medications (drugs that stress the liver), discuss cinnamon with your pharmacist.

Use the tool on this page to check your exact medications.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFormula with limited ingredient disclosure with no established evidence rating for its marketed use. Moderate medication interactions have been identified, and safety information is well characterized.

Ultracidal is a potent concentrate of three plant oils with the most serious concern being its interaction with diabetes medications and blood thinners. If you take any prescription medication—especially for blood sugar control or clotting—run it through the interaction checker on this page before starting.

Talk to your pharmacist about whether concentrated oils are right for you and what evidence actually supports your intended use.

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 Jul 21, 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 Ultracidal, straight from the product label.

Brand Physician's Strength
Net contents 1 Fluid Ounce(s); 30 mL
Market status On market
Date entered into DSLD Jul 21, 2022
DSLD ID 268997
Product type Botanical
Supplement form Liquid
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Kosher
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 Ultracidal by Physician's Strength, 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:
10 Drop(s)
Maximum serving Sizes:
10 Drop(s)
Servings per container
86
IngredientAmount% DV
Clove bud Oil0 NP--
Cinnamon Bark Oil0 NP--
Proprietary Blend240 mg--
Oregano Oil P73, Wild0 NP--

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: Take 10 drops twice daily under the tongue or in juice, water. May also be used topically.

Precautions

Keep away from the genitals, eyes, and out of reach of children.

Keep away from the genitals, eyes, and out of reach of children.

Formula

Ultracidal is the only wild-source, high-carvacrol oregano oil available. With the addition of cinnamon, blac seed, and clove bud oils Ultracidal is the ideal formula for healthy immune support. Also take it for a healthy, powerful whole body cellular response.

84% wild carvacrol

CRC Kosher

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

Healthy immune support

Doctor's formula

FDA Statement of Identity

Dietary Supplement

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

See for yourself

Ultracidal by Physician's Strength label

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

Ultracidal 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 Ultracidal by Physician's Strength

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

Serving size10 Drop(s) Dosage formLiquid Servings per container86 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

240 mg per serving Form: Black Seed Oil, Extra Virgin Olive Oil
Interaction report

Ultracidal by Physician's Strength Drug Interactions

Want to check YOUR meds against Ultracidal?

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
1,129Drugs
1,129 Moderate

Ingredients driving the most interactions

Clove bud Oil 977
Cinnamon Bark Oil 442
Oregano Oil P73, Wild 208

Individual Drug Interactions

The ingredients in Ultracidal interact with 1,129 drugs. Click any drug to see the details.

3 of the 3 ingredients in Ultracidal interact with drugs. Each result below shows which ingredient is responsible. Clove bud Oil Cinnamon Bark Oil Oregano Oil P73, Wild

Each ingredient & the kinds of drugs it affects

For each ingredient in Ultracidal 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.

Clove bud Oil7 drug types · 977 drugs

Antidiabetes Drugs

Theoretically, concomitant use of clove extracts with antidiabetes drugs might increase the risk of hypoglycemia.
Clinical and laboratory research suggest that polyphenol extracts from clove flower buds might lower blood glucose levels. Dosing adjustments for insulin or oral hypoglycemic agents may be necessary when taken with clove. Monitor blood glucose levels closely.

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

Theoretically, concomitant use of clove may increase levels of drugs metabolized by CYP1A2.
In vitro research shows that eugenol, the principal constituent of clove, can inhibit CYP1A2 in a dose-dependent manner,. This effect has not been reported in humans.

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

Theoretically, concomitant use of clove may increase levels of drugs metabolized by CYP2C9.
In vitro research shows that eugenol, the principal constituent of clove, inhibits CYP2C9 in a dose-dependent manner. This effect has not been reported in humans.

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

Theoretically, concomitant use of clove may increase levels of drugs metabolized by CYP2D6.
In vitro research shows that eugenol, the principal constituent of clove, can inhibit CYP2D6 in a dose-dependent manner. This effect has not been reported in humans.

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

Theoretically, concomitant use of clove may increase levels of drugs metabolized by CYP3A4.
In vitro research shows that eugenol, the principal constituent of clove, can inhibit CYP3A4 in a dose-dependent manner. This effect has not been reported in humans.

Likelihood Possible Evidence D
Anticoagulant/Antiplatelet Drugs

Theoretically, clove oil may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Laboratory research suggests that eugenol, a constituent of clove, has antiplatelet activity. This interaction has not been reported in humans.

Likelihood Unlikely Evidence D
Ibuprofen (Advil, Others)

Theoretically, topical application of clove oil with ibuprofen might increase the absorption and side effects of topical ibuprofen.
Laboratory research shows that topical application of clove oil increases the absorption of topical ibuprofen. This interaction has not been reported in humans.

Likelihood Possible Evidence D
Clove bud Oil full monograph & interactions

Cinnamon Bark Oil2 drug types · 442 drugs

Antidiabetes Drugs

Theoretically, cassia cinnamon may have additive effects with antidiabetes drugs.
Cassia cinnamon may lower blood glucose levels, and have additive effects in patients treated with antidiabetic agents. Dose adjustments to diabetes medications might be necessary.

Likelihood Possible Evidence B
Hepatotoxic Drugs

Theoretically, large doses of cassia cinnamon might cause additive effects when used with hepatotoxic drugs.
There is some concern that ingesting large amounts of cassia cinnamon for an extended duration might cause hepatotoxicity in some people. Cassia cinnamon contains coumarin, which can cause hepatotoxicity in animal models. In humans, very high doses of coumarin from 50-7000 mg/day can result in hepatotoxicity that resolves when coumarin use is discontinued. Lower amounts might also cause liver problems in sensitive people, such as those with liver disease or those taking potentially hepatotoxic agents.

Likelihood Possible Evidence D
Cinnamon Bark Oil full monograph & interactions

Oregano Oil P73, Wild2 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 P73, Wild full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Ultracidal, from the product label.

Physician's Strength

See all Physician's Strength products
Name
Physician's Strength
Street Address
13900 W. Polo Trail Drive
City
Lake Forest
State
IL
ZipCode
60045
Web Address
www.physicians-strength.com
Pharmacist Counseling Corner

Ultracidal by Physician's Strength: Common Questions

Does Ultracidal by Physician's Strength interact with any medications?
Yes. Based on its ingredients, Ultracidal has a known interaction with 1,129 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Ultracidal 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.
Is Ultracidal safe to use while pregnant or breastfeeding?
Clove oil and cinnamon bark oil are rated likely safe in pregnancy and lactation at normal food amounts. However, oregano oil has no safety data available for pregnancy, and the facts advise against medicinal or supplement amounts during pregnancy—food amounts are likely fine. Since this product contains concentrated oils, talk with your doctor or pharmacist before using it while pregnant or nursing.
Can I use this if I take blood thinners like warfarin?
Both clove oil and oregano oil may theoretically increase bleeding risk based on laboratory evidence that they have antiplatelet activity. This hasn't been reported in actual patients, but it's important enough that you should check with your pharmacist or doctor before starting Ultracidal if you're on blood thinners or antiplatelet drugs.
Will this lower my blood sugar if I take insulin or diabetes pills?
Yes—all three ingredients in Ultracidal may lower blood glucose levels. If you're on antidiabetes medications, this product could increase your risk of low blood sugar, so dose adjustments to your diabetes medication may be necessary. You'll need to monitor your blood sugar closely and talk with your doctor before starting.
What are the side effects of clove oil in this product?
At food spice doses, clove is well tolerated. Topically, clove may cause burning, itching, tingling, contact dermatitis, or mucous membrane irritation. Orally, the most serious rare effect is liver failure—but concentrated clove oil is especially risky in small children (5–10 mL can be toxic). When inhaled, clove may raise blood pressure and heart rate.
Is this product proven to work for cough or pain?
No. The evidence for clove oil on cough and acute pain is insufficient. Cinnamon and oregano have insufficient evidence for most conditions they're used for. Clove shows possibly effective evidence only for ventilator-associated pneumonia. If you're buying this for a specific health goal, ask your pharmacist what the science actually supports.
Can oregano oil cause allergic reactions?
Yes. Rare serious allergic reactions, including anaphylaxis (a life-threatening reaction), have been reported with oregano. Oregano can also cause allergic contact dermatitis and, at concentrations above 1%, may irritate mucous membranes. If you have a known allergy to plants in the mint family (Lamiaceae), use caution.

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.

Ultracidal label
Go deeper

The Full Monographs Behind Ultracidal’s Ingredients

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

Herb & supplement monograph

Clove

Interacts with 977 drugs

Clove is a common cooking spice that is also used in traditional medicine, especially as a topical numbing agent for tooth pain thanks to its main compound, eugenol. Food amounts are general...

Read the full Clove monograph → Herb & supplement monograph

Cassia Cinnamon

Interacts with 442 drugs

Cassia cinnamon is the common, inexpensive cinnamon used in cooking, and it is also taken as a supplement, most often for blood sugar support. The evidence for its health benefits is mixed a...

Read the full Cassia Cinnamon 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 →
Sources

Sources & How We Checked

Ultracidal'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 58 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.

Clove 26 references
  1. The Review of Natural Products by Facts and Comparisons. St. Louis, MO: Wolters Kluwer Co., 1999.
  2. Electronic Code of Federal Regulations. Title 21. Part 182 -- Substances Generally Recognized As Safe. Available at: https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?CFRPart=182
  3. Kanerva L, Estlander T, Jolanki R. Occupational allergic contact dermatitis from spices. Contact Dermatitis 1996;35:157-62. PubMed
  4. Chen SJ, Wang MH, Chen IJ. Antiplatelet and calcium inhibitory properties of eugenol and sodium eugenol acetate. Gen Pharmacol 1996;27:629-33. PubMed
  5. Malson JL, Lee EM, Murty R, et al. Clove cigarette smoking: biochemical, physiological, and subjective effects. Pharmacol Biochem Behav 2003;74:739-45. PubMed
  6. Kirsch CM, Yenokida GG, Jensen WA, et al. Non-cardiogenic pulmonary oedema due to the intravenous administration of clove oil. Thorax 1990;45:235-6. PubMed
  7. Pallares, D. E. Link between clove cigarettes and urticaria? Postgrad.Med 10-1-1999;106(4):153. PubMed
  8. Barnard, D. R. Repellency of essential oils to mosquitoes (Diptera: Culicidae). J Med Entomol. 1999;36(5):625-629. PubMed
  9. Sanchez-Perez, J. and Garcia-Diez, A. Occupational allergic contact dermatitis from eugenol, oil of cinnamon and oil of cloves in a physiotherapist. Contact Dermatitis 1999;41(6):346-347. PubMed
  10. Andersen, K. E., Johansen, J. D., Bruze, M., Frosch, P. J., Goossens, A., Lepoittevin, J. P., Rastogi, S., White, I., and Menne, T. The time-dose-response relationship for elicitation of contact dermatitis in isoeugenol allergic individuals. Toxicol.Appl PubMed
  11. Alqareer, A., Alyahya, A., and Andersson, L. The effect of clove and benzocaine versus placebo as topical anesthetics. J Dent 2006;34(10):747-750. PubMed
  12. Lane, B. W., Ellenhorn, M. J., Hulbert, T. V., and McCarron, M. Clove oil ingestion in an infant. Hum.Exp Toxicol. 1991;10(4):291-294. PubMed
  13. Quirce, S., Fernandez-Nieto, M., del, Pozo, V, Sastre, B., and Sastre, J. Occupational asthma and rhinitis caused by eugenol in a hairdresser. Allergy 2008;63(1):137-138. PubMed
  14. Srivastava, K. C. and Malhotra, N. Acetyl eugenol, a component of oil of cloves (Syzygium aromaticum L.) inhibits aggregation and alters arachidonic acid metabolism in human blood platelets. Prostaglandins Leukot.Essent.Fatty Acids 1991;42(1):73-81. PubMed
  15. Dyrbye, B. A., Dubois, L., Vink, R., and Horn, J. A patient with clove oil intoxication. Anaesth.Intensive Care 2012;40(2):365-366.
  16. Guidotti, T. L., Laing, L., and Prakash, U. B. Clove cigarettes. The basis for concern regarding health effects. West J Med 1989;151(2):220-228.
  17. Anonymous. Evaluation of the health hazard of clove cigarettes. Council on Scientific Affairs. JAMA 12-23-1988;260(24):3641-3644. DOI
  18. Romaguera, C., Alomar, A., Camarasa, J. M., Garcia, Bravo B., Garcia, Perez A., Grimalt, F., Guerra, P., Lopez, Gorretcher B., Pascual, A. M., Miranda, A., and . Contact dermatitis in children. Contact Dermatitis 1985;12(5):283-284. PubMed
  19. Hackett, P. H., Rodriguez, G., and Roach, R. C. Clove cigarettes and high-altitude pulmonary edema. JAMA 6-28-1985;253(24):3551-3552. DOI
  20. Isaacs, G. Permanent local anaesthesia and anhidrosis after clove oil spillage. Lancet 4-16-1983;1(8329):882. PubMed
  21. Saeed, S. A. and Gilani, A. H. Antithrombotic activity of clove oil. J Pak Med Assoc 1994;44(5):112-115.
  22. Hartnoll, G., Moore, D., and Douek, D. Near fatal ingestion of oil of cloves. Arch.Dis Child 1993;69(3):392-393. PubMed
  23. Srivastava, K. C. Antiplatelet principles from a food spice clove (Syzygium aromaticum L) [corrected]. Prostaglandins Leukot.Essent.Fatty Acids 1993;48(5):363-372.
  24. Jiang Q, Wu Y, Zhang H, et al. Development of essential oils as skin permeation enhancers: penetration enhancement effect and mechanism of action. Pharmaceutical Biol. 2017;55(1):1592-1600. PubMed
  25. Mohan R, Jose S, Mulakkal J, Karpinsky-Semper D, Swick AG, Krishnakumar IM. Water-soluble polyphenol-rich clove extract lowers pre- and post-prandial blood glucose levels in healthy and prediabetic volunteers: an open label pilot study. BMC Complement Alt PubMed
  26. Alharbi NFM, Ahad A, Bin Jardan YA, Al-Jenoobi FI. Effect of eugenol on cytochrome P450 1A2, 2C9, 2D6, and 3A4 activity in human liver microsomes. Saudi Pharm J 2024;32(7):102118. PubMed

See these in context on the Clove monograph →

Cassia Cinnamon 20 references
  1. Electronic Code of Federal Regulations. Title 21. Part 182 -- Substances Generally Recognized As Safe. Available at: https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?CFRPart=182
  2. Khan A, Safdar M, Ali Khan M, et al. Cinnamon improves glucose and lipids of people with type 2 diabetes. Diabetes Care 2003;26:3215-8. PubMed
  3. De Benito V, Alzaga R. Occupational allergic contact dermatitis from cassia (Chinese cinnamon) as a flavouring agent in coffee. Contact Dermatitis 1999;40:165. PubMed
  4. Drake TE, Maibach HI. Allergic contact dermatitis and stomatitis caused by a cinnamic aldehyde-flavored toothpaste. Arch Dermatol 1976;112:202-3.
  5. Press release. Cinnamon capsules to reduce blood sugar are medicinal products! Efficacy has not been scientifically proven - some products contain high levels of coumarin. Federal Institute of Risk Assessment (BfM), Germany, November 11, 2006. Available a
  6. Felter SP, Vassallo JD, Carlton BD, Daston GP. A safety assessment of coumarin taking into account species-specificity of toxicokinetics. Food Chem Toxicol 2006;44:462-75. PubMed
  7. Crawford P. Effectiveness of cinnamon for lowering hemoglobin A1C in patients with type 2 diabetes: a randomized, controlled trial. J Am Board Fam Med 2009;22:507-12. PubMed
  8. Akilen, R., Tsiami, A., Devendra, D., and Robinson, N. Glycated haemoglobin and blood pressure-lowering effect of cinnamon in multi-ethnic Type 2 diabetic patients in the UK: a randomized, placebo-controlled, double-blind clinical trial. Diabet.Med. 2010; PubMed
  9. Lu T, Sheng H Wu J Cheng Y Zhu J Chen Y. Cinnamon extract improves fasting blood glucose and glycosylated hemoglobin level in Chinese patients with type 2 diabetes. Nutr Res. 2012;32(6):408-412. PubMed
  10. Choi, J., Lee, K. T., Ka, H., Jung, W. T., Jung, H. J., and Park, H. J. Constituents of the essential oil of the Cinnamomum cassia stem bark and the biological properties. Arch Pharm Res 2001;24(5):418-423.
  11. Altschuler JA, Casella SJ, MacKenzie TA, Curtis KM. The effect of cinnamon on A1C among adolescents with type 1 diabetes. Diabetes Care 2007;30(4):813-6. PubMed
  12. Stoecker BR, Zhan Z, Luo R, et al. Cinnamon extract lowers blood glucose in hyperglycemic subjects. FASEB J. 2010;22:722.1 (Abstract only). DOI
  13. Admani S, Hill H, Jacob SE. Cinnamon Sugar Scrub Dermatitis: "Natural" Is Not Always Best. Pediatr Dermatol. 2017;34(1):e42-e43. PubMed
  14. Isaac-Renton M, Li MK, Parsons LM. Cinnamon spice and everything not nice: many features of intraoral allergy to cinnamic aldehyde. Dermatitis. 2015;26(3):116-21. PubMed
  15. Vandersall A, Katta R. Eyelid dermatitis as a manifestation of systemic contact dermatitis to cinnamon. Dermatitis. 2015 Jul-Aug;26(4):189. PubMed
  16. Wickenberg J, Lindstedt S, Nilsson J, Hlebowicz J. Cassia cinnamon does not change the insulin sensitivity or the liver enzymes in subjects with impaired glucose tolerance. Nutr J 2014 Sep 24;13:96. PubMed
  17. Brancheau D, Patel B, Zughaib M. Do cinnamon supplements cause acute hepatitis? Am J Case Rep 2015;16:250-4. PubMed
  18. Shekarchizadeh-Esfahani P, Heydarpour F, Izadi F, Jalili C. The effect of cinnamon supplementation on liver enzymes in adults: A systematic review and meta-analysis of randomized controlled trials. Complement Ther Med 2021;58:102699. PubMed
  19. Bernaola J, Valverde-Monge M, Otal-Buesa M, Cullen D, Heras-Mendaza F. Cinnamon allergic contact cheilitis. Contact Dermatitis 2023;88(5):418-419. PubMed
  20. Patel K, Howard M, Tate B. Cheilitis caused by allergic contact dermatitis to cinnamon in chai tea: A case report. Contact Dermatitis 2023;88(3):239-240. PubMed

See these in context on the Cassia Cinnamon 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 →

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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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