In aromatherapy, this essential oil helps to clear the mind and focus concentration, while reducing swelling in the mucus membranes. It is very valuable in fighting respiratory problems, fighting inflammation and sore muscles, rheumatism, headaches and nervous exhaustion, while boosting wound and ulcer healing and soothing skin eruptions.
Oil properties
Eucalyptus has a clear, sharp, fresh and very distinctive smell, is pale yellow in color and watery in viscosity.
Origin of eucalyptus oil
The Australian Blue-gum can sometimes reaches a height of 100 meters (300 feet), making it one of the highest trees in the world. There are over 500 species of Eucalyptus trees, with tough long and narrow blue-green leaves, creamy white flowers and smooth pale bark.
The 'eu' and 'kalypto' means 'well' and 'covered' in Greek, referring to the cup-like membrane that covers the flower bud, which is thrown off as the flower expands.
The Australian Aborigines calls it 'kino' and they use the leaves to cover serious wounds. Eucalyptus oil was introduced to Europe in 1788, and the first oil exported to England was called 'Sydney peppermint'. It was extracted from Eucalyptus peperita which is a more industrial type of oil.
The tree uses a lot of water while growing and has been used to clear water-logged land, draining the water from swamps where malaria mosquito may be found. The tree was thought to prevent malaria in the past, due to this draining action.
Extraction 
Eucalyptus oil is extracted from the fresh or partially dried leaves and young twigs.
Chemical composition
The main chemical components of eucalyptus oil are a-pinene, b-pinene, a-phellandrene, 1,8-cineole, limonene, terpinen-4-ol, aromadendrene, epiglobulol, piperitone and globulol.
Precautions
Eucalyptus oil should be used with care and people with high blood pressure and epilepsy should avoid it. Excessive use of this oil may cause headaches.
Therapeutic properties
The therapeutic properties of eucalyptus oil are analgesic, anti-bacterial, anti-inflammatory, anti-neuralgic, anti-rheumatic, antiseptic, antispasmodic, antiviral, astringent, balsamic, cicatrisant, decongestant, deodorant, depurative, diuretic, expectorant, febrifuge, hypoglycaemic, rubefacient, stimulant, vermifuge and vulnerary.
 Uses 
Eucalyptus oil has a cooling and deodorizing effect on the body, helping with fevers, migraine and malaria. For the respiratory tract, it helps with coughs, asthma, throat infections, sinusitis and catarrhal conditions. It soothes inflammation and eases mucus, clearing the head from the stuffiness of colds and hay fever.
Eucalyptus oil is useful as a warming oil when used for muscular aches and pains, rheumatoid arthritis, sprains and poor circulation.
In skin care it can be used for burns, blisters, herpes, cuts, wounds, skin infections and insect bites. It can furthermore boost the immune system and is helpful in cases of chicken pox, colds, flu and measles.
Summary
Eucalyptus oil is very helpful when used for headaches, fevers, ailments of the respiratory tract, muscular aches and pains and in skin care. It has a soothing and calming effect on the whole body and helps with the immune system.
The oil is also effective against bacteria - especially staphylococci, and has a refreshing and stimulating action on the mind, helping to improve concentration.
·    Burners and vaporizers
    In vapor therapy, eucalyptus oil may be used for: frequent sneezing, hay fever, flu, respiratory problems, as an insect repellant, headaches and for helping to improve concentration.
·    Blended massage oil or in the bath
    Eucalyptus oil can be used in blended massage oil, or diluted in the bath, to assist with arthritis, asthma, bronchitis, mucous congestion, colds, headaches, rheumatism, sinusitis, catarrh, fatigue and muscular aches and pains.
·    In a cream or lotion
    Apart from giving pain relief to muscular spasms and rheumatism, eucalyptus oil can also help speed up the healing of slow healing wounds and ulcers, calm skin eruptions and clear congested skin.
·    Used neat or dab on with a bud
    Eucalyptus oil can be used neat on the skin for insect bites or wounds, but care should be taken when doing so.
·    Gargle
    When very diluted eucalyptus oil is added to a gargle, so it can be used for soothing a sore throat.
Although essential oils normally blend well together eucalyptus oil blends particularly well with benzoin, thyme, lavender, lemongrass, lemon and pine.