Oregano
Related Terms
- Anthocyanins, betulinic acid, catechin, carvacrol, cyanidin, cymene, dostenkraut (German), eugenol, flavonoids, gallic acid, Greek oregano, Italian oregano (Origanum x majoricum), kekik (Turkish), Lamiaceae (family), Mediterranean oregano, mountain mint, O. minutiflorum Hausskn, O. vulgare ssp. vulgare, oil of oregano, oregamax, oregano oil, oregano spirits, Oregpig?, Origani vulgaris herba, origano, origanoside, origanum, Origanum acutidens (Hand.-Mazz.) Ietswaart, Origanum compactum, Origanum compactum Benth., Origanum compactum L., Origanum cordifolium (Aucher et Montbret ex Benth.) Vogel, Origanum creticum, Origanum dayi Post, Origanum dubium, Origanum dubium Boiss., Origanum floribundum, Origanum heracleoticum, Origanum heracleoticum L., Origanum libanoticum, Origanum micranthum, Origanum microphyllum, Origanum microphyllum (Bentham) Vogel, Origanum minutiflorum, Origanum minutiflorum O. Schwarz & P.H. Davis, Origanum officinalis, Origanum onites, Origanum onites L., Origanum scabrum, Origanum syriacum, Origanum syriacum L., Origanum syriacum var. bevanii, Origanum tyttanthum, Origanum vulgare L. ssp. hirtum, Origanum vulgare L. ssp. hirtum Ietswaart, Origanum vulgare L. ssp. hirtum (Link) Ietswaart, Origanum vulgare ssp. virens, Origanum vulgare L. ssp. vulgare, Origanum x applii, Origanum x intercedens, Origanum x majoricum, P73 oreganol, phenolic glucosides, polyphenols, quercetin, Spanish oregano, Syrian oregano, Syrian oreganum, tannins, thymol, Toka oregano, Turkish oregano, Turkish Origanum acutidens, wild marjoram, wintersweet, zaatar.
- Note: This bottom line does not include marjoram (Origanum majorana). This is discussed in the marjoram bottom line. The main species of interest in this bottom line is Origanum vulgare. However, due to the nature of oregano and the use of more than one species in the commercial spice, other species are discussed.
Background
- Oregano is an herb that has been used to preserve and add flavor to food. The leaves, stems, and flowers have been used as medicine for menstrual, lung, and stomach or intestinal disorders.
- Modern herbalists recommend taking oregano oil by mouth or applying it to the skin to treat infection. Strong human evidence for any clinical use of oregano is lacking.
- Oregano is thought to have antifungal, antioxidant, antibacterial, and insect-repelling effects, although evidence is mixed. The antibacterial and antioxidant effects of oregano are of interest to the food industry as oregano may hold promise as a natural preservative.
Evidence Table
These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider. |
GRADE * |
These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider. |
GRADE * |
The use of an herbal infusion containing oregano has been studied for use after tooth removal in people with hemophilia, a bleeding disorder. More research is needed in this area.
|
C |
The use of an herbal infusion containing oregano has been studied for use after tooth removal in people with hemophilia, a bleeding disorder. More research is needed in this area.
|
C |
Early research suggests that oregano may improve cholesterol levels and heart disease risk. However, further study is needed before conclusions can be made.
|
C |
Early research suggests that oregano may improve cholesterol levels and heart disease risk. However, further study is needed before conclusions can be made.
|
C |
Early study shows that taking oregano oil by mouth for six weeks may help treat some parasite infections. While promising, further research is needed to confirm these results.
|
C |
Early study shows that taking oregano oil by mouth for six weeks may help treat some parasite infections. While promising, further research is needed to confirm these results.
|
C |
Early study suggests that an ointment containing oregano may improve color and scar softness as well as reduce bacteria. However, more research is needed in this field.
|
C |
Early study suggests that an ointment containing oregano may improve color and scar softness as well as reduce bacteria. However, more research is needed in this field.
|
C | * Key to grades
A: Strong scientific evidence for this use
B: Good scientific evidence for this use
C: Unclear scientific evidence for this use
D: Fair scientific evidence for this use (it may not work)
F: Strong scientific evidence against this use (it likley does not work)
| * Key to grades
A: Strong scientific evidence for this use
B: Good scientific evidence for this use
C: Unclear scientific evidence for this use
D: Fair scientific evidence for this use (it may not work)
F: Strong scientific evidence against this use (it likley does not work)
| Tradition / Theory
The below uses are based on tradition, scientific theories, or limited research. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider. There may be other proposed uses that are not listed below.
Dosing
Adults (18 years and older)
- Oregano has been taken by mouth in the following forms: capsules (containing 45 milligrams of pure oregano oil), 1-3 times daily with meals; 250-500 milligrams of leaf extract three times daily; 3-6 drops of oil, pure or diluted with olive oil, added to milk or juice 1-2 times daily; and a tea made from hot water and finely ground herb. Traditionally, 5-6 drops of oregano oil have been taken by mouth 2-3 times daily with sugar, and 1-4 drops of oregano tincture have been diluted in water and taken by mouth 2-3 times daily.
- For heart disease prevention, 25 milliliters of oregano distillate have been taken by mouth after each meal for three months.
- For the prevention of bleeding after tooth removal, 30 milliliters of an oregano infusion have been taken by mouth six times daily for 10 days.
- For parasites, 200 milligrams of oregano oil have been taken by mouth three times daily with meals for six weeks.
- For the common cold, 1-3 drops of oregano oil have been taken by mouth in a teaspoon of olive oil.
- For cosmetic uses, oregano oil has been added to commercial shampoo and applied to the hair for a few minutes before rinsing.
- For wound healing, a 3 percent oregano extract ointment has been applied to the skin twice daily for 10-14 days.
Safety
The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.
Interactions
Interactions with Drugs
- Oregano may increase the risk of bleeding when taken with drugs that increase the risk of bleeding. Some examples include aspirin, anticoagulants ("blood thinners") such as warfarin (Coumadin?) or heparin, anti-platelet drugs such as clopidogrel (Plavix?), and non-steroidal anti-inflammatory drugs such as ibuprofen (Motrin?, Advil?) or naproxen (Naprosyn?, Aleve?).
- Oregano may lower blood sugar levels. Caution is advised when using medications that may also lower blood sugar. People taking drugs for diabetes by mouth or insulin should be monitored closely by a qualified healthcare professional, including a pharmacist. Medication adjustments may be necessary.
- Oregano may cause low blood pressure. Caution is advised in people taking drugs that lower blood pressure.
- Oregano may interfere with the way the body processes certain drugs using the liver's "cytochrome P450" enzyme system. As a result, the levels of these drugs may be altered in the blood, and may cause altered effects or potentially serious adverse reactions. People using any medications should check the package insert, and speak with a qualified healthcare professional, including a pharmacist, about possible interactions.
- Oregano may also interact with agents that affect blood vessel width, agents that affect the immune system, agents that cause abortion, agents that prevent blood vessel formation, agents that prevent muscle spasms, agents that treat skin disorders, agents that treat stomach and intestinal disorders, Alzheimer's agents, anti-anxiety agents, antibiotics, anticancer agents, anti-diarrhea agents, antifungal agents, antihistamines, anti-inflammatory agents, anti-malaria agents, anti-parasite agents, anti-protozoa agents, antiviral agents, central nervous system (CNS) depressants, cholesterol-lowering agents, fertility agents, furosemide, and hormonal agents.
Attribution
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This information is based on a systematic review of scientific literature edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com).
Bibliography
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