Oregano oil has long been known as one of the storngest anitbacterial oils. The disinfectant and antibacterial properties of oregano essential oil were first recognized in ancient Greece where it was often used for treating bacterial infections on the skin or wounds. It is also an expectorant, which loosens up or helps eliminate the uncomfortable buildups of mucus and phlegm in the respiratory tracts and sinuses. It is also antiviral and antifungal.
It is known in aromatherapy as a "hot oile", and must be diluted carefully in its application.