What is it?
Oregano has olive-green leaves and purple flowers. It is closely related to other herbs, including mint, thyme, marjoram, and basil. Oregano contains chemicals that might help reduce cough. Oregano also might help with digestion and with fighting against some bacteria and viruses.
People use oregano for wound healing, parasite infections, and many other conditions, but there is no good scientific evidence to support these uses.
How effective is it?
There is interest in using oregano for a number of purposes, but there isn't enough reliable information to say whether it might be helpful.
Is it safe?
When applied to the skin: There isn't enough reliable information to know if oregano oil is safe to apply to the skin. It may cause irritation when applied in concentrations greater than 1%.
Special precautions & warnings:Pregnancy: Oregano is possibly unsafe when taken by mouth in medicinal amounts during pregnancy. There is concern that taking oregano in amounts larger than food amounts might cause miscarriage. Stay on the safe side and stick to food amounts.
Breast-feeding: There isn't enough reliable information to know if large amounts of oregano are safe to use when breast-feeding. Stay on the safe side and stick to food amounts.
Allergies: Oregano can cause reactions in people allergic to Lamiaceae family plants, including basil, hyssop, lavender, marjoram, mint, and sage.
Surgery: Large doses of oregano might increase the risk of bleeding. People who use large doses of oregano should stop taking oregano 2 weeks before surgery.
Are there interactions with medications?
- Medications for diabetes (Antidiabetes drugs)
- Oregano might lower blood sugar levels. Taking oregano along with diabetes medications might cause blood sugar to drop too low. Monitor your blood sugar closely.
- Medications that slow blood clotting (Anticoagulant / Antiplatelet drugs)
- Oregano might slow blood clotting. Taking oregano along with medications that also slow blood clotting might increase the risk of bruising and bleeding.
Are there interactions with herbs and supplements?
- Oregano might decrease the absorption of copper into the body. But it isn't clear if this is a big concern.
- Herbs and supplements that might lower blood sugar
- Oregano might lower blood sugar. Taking it with other supplements with similar effects might lower blood sugar too much. Examples of supplements with this effect include aloe, bitter melon, cassia cinnamon, chromium, and prickly pear cactus.
- Herbs and supplements that might slow blood clotting
- Oregano might slow blood clotting and increase the risk of bleeding. Taking it with other supplements with similar effects might increase the risk of bleeding in some people. Examples of supplements with this effect include garlic, ginger, ginkgo, nattokinase, and Panax ginseng.
- Oregano might decrease the absorption of iron into the body. But it isn't clear if this is a big concern.
- Oregano might decrease the absorption of zinc into the body. But it isn't clear if this is a big concern.
Are there interactions with foods?
- There are no known interactions with foods.
How is it typically used?
To learn more about how this article was written, please see the Natural Medicines Comprehensive Database methodology.
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