Eucalyptus refers to one of many species of flowering tree in the myrtle family, most of which are native to Australia. Eucalyptus is famous for its volatile oils – the Blue Mountains in Australia take their name from the fragrant haze which hangs over eucalyptus forests during hot weather.
Strongly scented eucalyptus oil is steam distilled from the leaves of the tree, and has many uses. It is used in small quantities as a food flavouring, and as a fragrance. It also has bio pesticide and insect repellent properties.
Eucalyptus contains eucalyptol, a camphor-like substance which is a cough suppressant and decongestant, and which also has antimicrobial properties and a slight local anaesthetic effect. It also contains cineole, which can kill the bacteria which cause bad breath, so eucalyptus is often used in mouthwash.
As an essential oil, eucalyptus can be steam inhaled to help relieve coughs and colds. As an aromatherapy oil, it is thought to have a stimulating effect, and may help to relieve depression.
Diluted oil can also be applied topically to help disinfect and heal skin wounds, and to treat fungal infections. Eucalyptus oil is also believed to help relieve joint pain when massaged into the skin.