Oregano Interactions Overview

Does Oregano (Or Oregano Oil) Interact With Any Drugs?

While oregano (and oregano oil) supplements are generally considered safe, they have a theoretical interaction with certain medications, including anticoagulant/antiplatelet drugs and anti-diabetes drugs.

Anticoagulant; Antiplatelet Drugs

Anticoagulants and antiplatelet drugs work by slowing down or preventing blood clotting. While they are essential medications for individuals with certain conditions, they come with an increased risk of bleeding.

Some studies have reported that oregano oil may also increase the risk of bleeding, as it contains compounds that have antithrombin activity and can inhibit platelet aggregation.

Therefore, taking oregano oil along with anticoagulants or antiplatelet drugs may increase the risk of bleeding, bruising, and other adverse effects.

One of the compounds found in oregano oil, aristolochic acid, has been shown to have antithrombin activity in vitro (i.e., lab) research.

Antithrombin is a protein that inhibits the coagulation cascade, which is involved in the formation of blood clots. By inhibiting antithrombin, aristolochic acid may increase the risk of bleeding.

In addition, oregano oil has been shown to inhibit arachidonic acid-induced and ADP-induced platelet aggregation in vitro studies.

It is important to note that the evidence supporting an interaction between oregano oil and anticoagulant/antiplatelet drugs is largely theoretical and based on in vitro studies. Evidence in human studies is lacking.

However, it is still recommended to be cautious when taking oregano oil supplements with any other drug that increases the risk of bleeding.

Anti-Diabetic Drugs

Several studies suggest that oregano supplements may help lower blood glucose (i.e., sugar) levels. In vitro and animal research has shown that oregano extracts might stimulate glucose uptake and reduce blood glucose levels.

Additionally, a study on diabetic rats found that oregano oil significantly decreased blood glucose levels, increased insulin levels, and improved glucose tolerance.

Therefore, based on the available evidence, combining oregano oil with antidiabetic drugs could potentially cause blood sugar levels to drop too low, leading to hypoglycemia.

However, it is important to note that studies reporting that oregano can reduce blood glucose levels have not reported it causing hypoglycemia.

Nevertheless, a theoretical interaction remains here due to the potential additive blood-sugar-lowering effects of oregano and certain antidiabetic drugs.

References

• Anti-hyperglycaemic activity of the aqueous extract of Origanum vulgare growing wild in Tafilalet region. PubMed
• Inhibitory effect of clonal oregano extracts against porcine pancreatic amylase in vitro. PubMed
• Antithrombin activity of some constituents from Origanum vulgare. PubMed
• Comparative screening of plant essential oils: phenylpropanoid moiety as basic core for antiplatelet activity. PubMed

Are Oregano Oil Supplements Standardized?

Oregano oil supplements are available in various forms, including capsules, softgels, liquids, and essential oils. Many are standardized for certain constituents.

The two primary active compounds in oregano oil are carvacrol and thymol, which are responsible for the oil's antimicrobial, antifungal, and antioxidant properties. The standardization of oregano oil supplements is typically based on the carvacrol content, which can range from 30% to 85%.

What Is P73?

Oregano P73 is a patented blend of oregano oil developed by North American Herb and Spice (NAHS). Their line of oregano oil supplements is marketed for their P73 form of oregano.

The name P73 stands for "Polyphenol 73," which refers to the high level of phenolic compounds, including carvacrol and thymol, found in the oregano oil blend.

According to the manufacturer, the oregano P73 blend is derived from wild oregano plants that grow naturally in the Mediterranean region, which are purported to have a higher potency and effectiveness compared to commercially cultivated oregano.

What Is Carvacrol?

Carvacrol is a naturally occurring monoterpene phenol, and a major constituent of oregano. In fact, it is responsible for much of its characteristic aroma and flavor. Many oregano supplements are standardized for their carvacrol content.

Carvacrol is known for its antibacterial, antifungal, antiviral, anti-inflammatory, and antioxidant properties. It has been studied for its potential therapeutic applications in a variety of conditions, including infections and allergies.

In vitro and animal studies have shown that carvacrol exhibits a broad spectrum of antimicrobial activity against a variety of bacteria, fungi, and viruses. It has been shown to inhibit the growth of bacteria such as Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa, as well as fungi such as Candida albicans and Aspergillus niger.

Carvacrol has also been shown to have antiviral activity against herpes simplex virus type 1 and influenza A virus.

Additionally, carvacrol has been found to have anti-inflammatory properties (it may inhibit the production of pro-inflammatory cytokines and enzymes, such as interleukin-1β and cyclooxygenase-2), which may make it useful in the treatment of conditions such as rheumatoid arthritis, inflammatory bowel disease, and asthma.

References

• Essential oil diversity of European Origanum vulgare L. (Lamiaceae).  PubMed
• GC-MS analysis of essential oils from some Greek aromatic plants and their fungitoxicity on Penicillium digitatum. PubMed
• Antimicrobial activity of essential oils of cultivated oregano (Origanum vulgare), sage (Salvia officinalis), and thyme (Thymus vulgaris) against clinical isolates of Escherichia coli, Klebsiella oxytoca, and Klebsiella pneumoniae. PubMed
• Antimicrobial activity of essential oils and other plant extracts. PubMed
  

Additional Details

Is Oregano Safe? Are There Any Warnings?

Oregano, a perennial herb with olive-green leaves and purple flowers, is generally safe for consumption in normal food amounts. It belongs to the same family as mint, thyme, basil, and other herbs. Oregano is commonly used as a culinary herb and is native to Europe and the Mediterranean region. However, when used in larger amounts or for medicinal purposes, there is limited information available about its safety.

Pregnant women should avoid using oregano in medicinal amounts as it is believed to have effects that could lead to abortion or changes in menstruation. For breastfeeding women, it is recommended to stick to the amounts commonly found in food and avoid larger medicinal amounts.

While oregano is generally well-tolerated, there are a few potential adverse effects. In some cases, it may cause gastrointestinal upset when consumed orally. When applied topically, oregano oil can cause dermatitis in sensitive individuals. Serious allergic reactions, although rare, can occur orally, leading to conditions like anaphylaxis.

How Is Oregano Thought to Work? What Is the Mechanism of Action?

Oregano contains essential oil extracted from its leaves and other above-ground parts. The essential oil composition can vary depending on the subspecies of oregano and growing conditions. It is rich in volatile phenolic monoterpenes, including carvacrol, thymol, and other compounds such as beta-fenchyl alcohol, delta-terpineol, gamma-terpinene, and alpha-terpinene. These components contribute to oregano's medicinal properties.

Oregano's antibacterial effects are attributed to its essential oil, particularly carvacrol and thymol. These compounds have been shown to inhibit the growth of various bacteria, including Staphylococcus aureus, Escherichia coli, and Salmonella enterica. They disrupt the structure and function of bacterial cell membranes, leading to cell damage and leakage of essential ions. Oregano oil also exhibits antifungal properties, inhibiting the growth of Candida albicans and other fungi.

In animal studies, oregano has demonstrated antidiabetic effects by lowering blood glucose levels. It may achieve this by inhibiting enzymes involved in starch breakdown, reducing the conversion of starch to glucose. Oregano oil has also shown antiviral activity against influenza virus H1N1 in laboratory settings.

Pharmacokinetics

There is limited information available about the pharmacokinetics of oregano, which refers to its absorption, distribution, metabolism, and excretion in the body. Further research is needed to understand how the body processes oregano and its active compounds.

Interaction Overview (See Below for Full List)

Oregano may interact with certain drugs and supplements, so caution is advised when combining them. Oregano might increase the risk of bleeding when taken with anticoagulant or antiplatelet drugs. It may also pose a moderate risk of hypoglycemia when taken with antidiabetes drugs. Oregano could potentially have interactions with other herbs and supplements, affecting the absorption of copper, iron, and zinc, as well as exerting antiplatelet and hypoglycemic effects.

Common Side Effects to Watch For

While oregano is generally well-tolerated, some common side effects to watch for include gastrointestinal upset when taken orally and dermatitis when applied topically. These side effects are typically mild and occur in sensitive individuals.

Drugs that interact with Oregano