Eucalyptus Oil… Not Just for Koala Bears!

Eucalyptus Oil... Not Just for Koala Bears!The aborigines of Australia were the first humans to discover the healing qualities of the eucalyptus tree, but the koala, Australia’s lovable herbivorous marsupial, was actually the first mammal to discover the amazing leaves of the eucalyptus. A koala spends at least three of its five active hours eating the leaves of several varieties of eucalyptus trees because they are low in protein and high in phenolic compounds, which are powerful antioxidants [1]. Eucalyptus leaves are also rich in terpene compounds, which are the primary constituents in the essential oil of the eucalyptus tree. The aborigines undoubtedly noticed the affect of eucalyptus on the koala, and began to use the leaves in order to benefit healthwise. They used these species for antiseptic, repellent, and flavoring purposes.

Almost three thousand tons of eucalyptus oil is produced every year by China, South Africa, Brazil, Chile, Australia, Spain, and Portugal. These countries generally produce three types of oil depending on the end use, but the most popular oil of eucalyptus (Eucalyptus globulus) is the cineole-based version, which has a spicy smell reminiscent of camphor and a cooling effect [2]. The medicinal uses of this naturally fragrant oil are well known and the fortification it provides to the immune system is considered a vital element in aromatherapy applications.

The genus Eucalyptus contains at least 700 species, not all of which produce an essential oil that is suitable for aromatherapy. Eucalyptus globulus, which is harvested to make the most popular eucalyptus oil in the world, contains mainly the cooling, antibacterial compound 1,8-cineole; this compound is also called eucalyptol because it was first isolated from the eucalyptus tree [3]. Other eucalyptus species produce oils that are based on other compounds, such as phellandrene and piperitine [3].

Although the healing powers of eucalyptus oil were known to Australian aborigines for millennia, Europeans learned of the oil’s benefits fairly recently. A refined eucalyptus oil was first isolated from Eucalyptus piperita by British physicians in the 1770s, who used the oil to treat convicts and Marines [3]. At the time, colonists to Australia called eucalyptus essential oil “Sydney peppermint”, because its minty, camphoraceous smell reminded them of peppermint oil. Joseph Bosisto was the colonist who came up with the idea of commercializing eucalyptus oil and selling it overseas, and Bosisto’s “Oil of Eucalyptus” can still be bought under that brand today [3].

The properties of pure eucalyptus oil are anti-inflammatory, analgesic, anti-spasmodic, and expectorant [4]. Small amounts of eucalyptus oil or 1,8-cineole are approved additives to cough drops, throat lozenges, sprays and inhalants because the compounds in eucalyptus relieve symptoms of cold and flu such as respiratory congestion, irritation, and the impulse to cough [2]. 1,8-cineole has also been shown to kill bacteria in the respiratory tract [5]. Eucalyptus essential oil or 1,8-cineole can also be added to liniments designed for use on sore muscles and joints, since the cooling action of the oil eases pain and reduces tissue inflammation [6].

Eucalyptus oil also has the ability to affect monocytes, which are a type of white blood cell that are an important aspect of the human immune system [7]. Monocytes have two main functions: first, they help initiate the defense systems when free radicals attach themselves to cells and begin to damage them, and second, they respond to inflammation and infection in the tissues, so the immune system can identify and divide the cells, and then regenerate new cell growth.

Although eucalyptus oil is generally non-sensitizing, non-toxic and non-irritating, it should always be diluted for topical applications and should never be taken internally. The eucalytpus oil in cough drops and other oral medications has undergone a careful double-distillation process to render it safe as a food ingredient.

A fortified immune system is the foundation for an active lifestyle, as well as for an extended life cycle, so take a hint from the happy, healthy koala bear and make the benefits of pure eucalyptus oil a part of your daily life!


1. Rice-Evans, Catherine, Nicholas Miller, and George Paganga. April 1997. “Antioxidant properties of phenolic compounds”. Trends in Plant Science 2 (4): 152-59.

2. “Eucalyptol: Medicinal Uses”. Wikipedia. Last modified June 19th, 2014.

3. “Eucalyptus Oil”. Wikipedia. Last modified March 31st, 2014.

4. “Essential OIl Chemistry: Oils High in 1,8-Cineole”. The Aromahead Institute: Aromatherapy Education and Resources. Last modified August 2nd, 2009.

5. Salari, M. H.; Amine, G.; Shirazi, M. H.; Hafezi, R.; Mohammadypour, M. (2006). “Antibacterial effects of Eucalyptus globulus leaf extract on pathogenic bacteria isolated from specimens of patients with respiratory tract disorders”. Clinical Microbiology and Infection 12 (2): 194–6.

6. Santos FA and VS Rao. 2000. “Anti-inflammatory and anti-nociceptive effects of 1,8-cineole: a terpenoid oxide present in many plant essential oils”. Phytotherapy Research 14: 240-44.

7. Juergens, Uwe R, Tanja Engelen, Kurt Racké, Meinolf Stöber, Adrian Gillissen, and Hans Vetter. October 2004. “Inhibitory activity of 1,8-cineole (eucalyptol) on cytokine production in cultured human lymphocytes and monocytes”. Pulmonary Pharmacology and Therapeutics 17 (5): 281-87.