Oregano is a perennial herb, growing from 20–80 cm tall, with opposite leaves 1–4 cm long. Oregano will grow in a pH range between 6.0 (mildly acidic) and 9.0 (strongly alkaline) with a preferred range between 6.0 and 8.0. The flowers are purple, 3–4 mm long, produced in erect spikes. It is sometimes called wild marjoram, and its close relative O. majorana is known as sweet marjoram.
Oregano contains polyphenols, including numerous flavones.In large quantities, such as might be obtained by ingesting the essential oil, O. vulgare is an emmenagogue and abortifacient.
In the myths of folk medicine, Hippocrates used oregano as an antiseptic, as well as a cure for stomach and respiratory ailments. A Cretan oregano (O. dictamnus) is still used today in Greece as a palliative for sore throat.In Austrian folk medicine, oregano was used internally (as tea) or externally (as ointment) for treatment of disorders of the gastrointestinal tract, respiratory tract, and nervous system.
In 2005, the US Federal Trade Commission brought legal action against a firm that had claimed oil of oregano treated colds and flu, and that oil of oregano taken orally treated and relieved bacterial and viral infections and their symptoms, saying the representations were false or were not substantiated at the time the representations were made, and that they were therefore a deceptive practice and false advertisements. The final stipulation on the matter said no representation as to any health benefit could be made without "…competent and reliable scientific evidence…".
