Health Benefits of Oregano Oil

This Essential Oil Boasts Antibacterial and Antiviral Properties

Oregano oil is an essential oil made from the oregano plant that is purported to have healing properties. Research shows oregano oil has antimicrobial, antiviral and antifungal properties. In addition compounds in oregano oil are also potent antioxidant, anti-inflammatory, antidiabetic, and cancer-suppressor agents.

In alternative medicine, oregano oil is touted as a natural remedy for a range of health issues. It also can be taken in a variety of ways. Here's how it may help:

  • When taken orally, oregano oil may help with indigestion and gastrointestinal illnesses, as well as respiratory illnesses. 
  • When used with steam and inhaled, oregano oil may provide benefits for sinus and chest congestion and related respiratory illnesses. 
  • When diluted and used topically, oregano oil may help treat fungal and bacterial infections. It can also be applied to the skin for the treatment of acne, athlete's foot, canker sores, psoriasis, rosacea, varicose veins, and warts.
ways to take oregano oil
Verywell / Alexandra Gordon

Health Benefits

Oregano oil has been widely studied in cell cultures and animal studies, but few scientific studies have tested its effects on human health. However, some preliminary research suggests that oregano oil may offer certain health benefits.


A combination of thyme and oregano oils shows promise in the treatment of colitis, a type of inflammatory bowel disease. An animal-based study published in Mediators of Inflammation found colitis-afflicted mice experienced a significant reduction in inflammation after treatment with the combination treatment.

Due to a lack of clinical trials, it's unknown whether a combination of thyme and oregano oils may be beneficial in treatments for colitis in humans.


In laboratory research, scientists have shown that oregano oil may help fight the growth of candida. A type of yeast that normally resides in the digestive tract and vagina, candida can contribute to a number of infections including oral thrush, skin infections, and vaginal yeast infections when its growth goes unchecked.

While findings from test-tube studies and animal-based research are promising, there is currently a lack of clinical trials demonstrating that oregano oil can help prevent or treat candida-related infections in humans.

Bacterial Infections

Preliminary research indicates that oregano oil may help protect against certain bacterial infections. A mouse study published in Toxicology Mechanisms and Methods showed that oregano oil may be useful for the prevention or treatment of Staphylococcus aureus infection.

Another study published in the Journal of Huazhong University of Science and Technology found oregano oil may be effective in destroying the bacteria associated with dysentery in mice. These studies, however, have not been replicated in humans.

Possible Side Effects

Taken in amounts regularly found in food, oregano and its essential oil are considered safe. There are some concerns about taking oregano oil in medicinal doses for certain populations. As with all essential oils, oregano should only be taken internally if directed by a healthcare professional.

  • Oregano may cause an allergic reaction in people who have an allergy to plants in the Lamiaceae family, which includes basil, mint, rosemary, sage, savory, marjoram, oregano, hyssop, thyme,
    lavender and perilla. 
  • Oregano oil taken in medicinal amounts should be avoided during pregnancy due to concerns about miscarriage.
  • People with bleeding disorders should not take oregano oil as it may increase the risk of bleeding. Similarly, discontinue use of oregano oil two weeks before scheduled surgery due to concerns over bleeding risk.
  • Oregano oil may decrease blood sugar in people with diabetes and should be used cautiously.

Mild side effects from ingesting oregano essential oil include stomach upset and irritation of the intestinal tract. When used topically, oregano essential oil should always be diluted. It may cause burning and skin irritation.


Oregano oil may interact with certain medications and supplements, and should not be taken with the following:

  • Antidiabetic drugs including glimepiride (Amaryl), glyburide (DiaBeta, Glynase PresTab, Micronase), insulin, metformin (Glucophage), pioglitazone (Actos), rosiglitazone (Avandia), and others. In addition, it should not be used with herbs and supplements that might lower blood sugar including alpha-lipoic acid, bitter melon, chromium, devil's claw, fenugreek, garlic, guar gum, horse chestnut, Panax ginseng, psyllium, Siberian ginseng, and others.
  • Anticoagulants including Some medications that slow blood clotting include aspirin, clopidogrel (Plavix), dabigatran (Pradaxa), dalteparin (Fragmin), enoxaparin (Lovenox), heparin, warfarin (Coumadin), and others. In addition, it should not be taken with herbs that interfere with blood clotting, including angelica, clove, danshen, garlic, ginger, ginkgo, Panax ginseng, horse chestnut, red clover, turmeric, and others.
  • Copper absorption may be decreased when taken with oregano oil.
  • Iron absorption may be decreased when taken with oregano oil.
  • Zinc absorption may be decreased when taken with oregano oil.

Dosage and Preparation

There is no recommended dose for oregano oil. If used topically, the oil should be diluted in a carrier oil to a less than 1 percent solution. According to the National Institutes of Health, there is not enough scientific research to determine a safe dose range for use in humans.

What to Look For

Essential oils are not regulated by the FDA and do not have to meet any purity standards. When purchasing essential oils, look for a supplier who either distill their own material or deals directly with reputable distillers and uses gas chromatography and mass spectrometry (GC/MS) to analyze the quality of the product.

When buying pure oregano essential oil, check the label for its Latin name, Origanum vulgare. No other oils ingredients should be listed. If you see another oil, such as fractionated coconut oil, jojoba oil, or sweet almond oil, the oregano oil is diluted and should not be used in a diffuser. 

Essential oils should be packaged in a dark amber or cobalt bottle and stored out of sunlight.

Other Questions

What is the difference between oregano oil, oregano essential oil, and oil of oregano?

Oregano oil is typically extra-virgin olive oil with oregano infused in the oil. This is not medicinal oregano, but cooking oregano. Both oregano essential oil and oil of oregano are used medicinally.

Oregano essential oil and oil of oregano are distilled from the oregano plant. Oil of oregano is sometimes sold in capsules that include a carrier oil to dilute the essential oil for ease of digestion.

Why do organic chicken farmers use oregano oil?

Oregano essential oil has antibacterial and anti-fungal properties. Some poultry farmers use oregano oil instead of commercial antibiotics to keep their flock healthy and prevent infections. Its use has been widely studied in farming and believed to be a safe, natural alternative to drugs.

A Word From Verywell

Due to the limited research, it's too soon to recommend oregano oil as a treatment for any condition. If you're considering using it, talk to your doctor to weigh the potential risks and benefits.

Keep in mind that alternative medicine should not be used as a substitute for standard care. Self-treating a condition and avoiding or delaying standard care may have serious consequences. 

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Article Sources
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