Eucalyptus essential oil is obtained from fresh leaves of the tall, evergreen eucalyptus tree. The tree, scientifically classified as Eucalyptus Globulus. Eucalyptus essential oil has antiseptic qualities because of its germicidal quality. Eucalyptus essential oil is effective for treating a number of respiratory problems including cold, cough, running nose, sore throat, asthma, nasal congestion, bronchitis, and sinusitis. Eucalyptus oil creates a cooling and refreshing effect. It can also be effective in the treatment of stress and mental disorders. Relieves Muscle Pain. Eucalyptus oil is also used for treating fever and reducing body temperature.