Oregano oil is taken by mouth to treat sinus pain, swine flu, allergies, arthritis and intestinal parasites, and it's applied to the skin to treat canker sores, ringworm, athlete's foot, acne and psoriasis among other conditions. The oil is extracted from a plant called oregano. The leaves of the plant are used to make medicine for treating respiratory tract disorders, gastrointestinal disorders and urinary tract infections.
Oregano contains a chemical that helps fight these conditions. It may also help increase bile flow to enhance digestion and fight against some foreign invaders in the body. Research on the use of oregano for treating various conditions is still ongoing. To treat intestinal parasites, a person needs to take oregano oil three times a day for six weeks, as stated by WebMD.
As of 2014, there is not enough information on oregano to advise clearly on its safety. It has been associated with stomach upset. People who are allergic to plants that belong to the Lamiaceae group should not use oregano oil. Pregnant women should not use the oil, as it may lead to miscarriage. It has also been linked to different conditions such as bleeding disorders, allergies and diabetes. It's necessary to consult a doctor before using oregano oil.