Eucalyptus globulus, also known as fever tree or gum tree, is an evergreen tree that is one of the most widely cultivated trees native to Australia. The leaves of the Eucalyptus globulus can be steam distilled to extract eucalyptus oil. Eucalyptus oil has a history of wide application, including use as a pharmaceutical, antiseptic, repellent, flavoring, and fragrance.

A primary component of eucalyptus leaf oil is eucalyptol, or 1,8-cineole, which accounts for 70 to 90 percent of the contents of this oil. Eucalyptol has antioxidant, anti-inflammatory, and pain-relieving effects. After topical application, it can help to reduce inflammation, muscle pain, soreness, and swelling. Eucalyptus leaf oil also has antimicrobial and antiseptic properties, which makes it an excellent ingredient for minor skin irritations such as cuts, burns, sores, and insect bites.