Eucalyptus oil (E. globulus Labillardiere, E. fructicetorum F. Von Mueller, E. smithii R.T. Baker)


Eucalyptus oil is used commonly as a decongestant and expectorant for upper respiratory tract infections or inflammations, as well as for various musculoskeletal conditions. The oil is found in numerous over-the-counter cough and cold lozenges as well as in inhalation vapors or topical ointments. Veterinarians use the oil topically for its reported antimicrobial activity. Other applications include as an aromatic in soaps or perfumes, as flavoring in foodstuffs or beverages, and as a dental or industrial solvent. High quality scientific evidence is currently lacking.
Eucalyptus oil contains 70-85% 1,8-cineole (eucalyptol), which is also present in other plant oils. Eucalyptol is used as an ingredient in some mouthwash and dental preparations, as an endodontic solvent, and may possess antimicrobial properties. Listerine® mouthrinse is a combination of essential oils (eucalyptol, menthol, thymol, methyl salicylate) that has been shown to be efficacious for the reduction of dental plaque and gingivitis.
Topical use or inhalation of eucalyptus oil at low concentrations may be safe, although significant and potentially lethal toxicity has been consistently reported with oral use and may occur with inhalation use as well. All routes of administration should be avoided in children.

Related Terms

1,8-cineole, aerial eucalyptus, Australian fever tree leaf, blauer gommibaum, blue gum, C10H18O, cajuputol, camphor oil, catheter oil, cider gum, cineole, Citriodiol®, crown gall, essence of eucalyptus rectifiee, essencia de eucalipto, eucalypti aetheroleum, eucalypti folium, eucalyptol, Eucalyptuscamaldulensis (Red gum), Eucalyptuscitriodora (Lemon-scented gum), Eucalyptuscoccifera (Tasmanian snow gum), Eucalyptusdalrympleana (Mountain gum), eucalyptus dried leaves, eucalyptus essential oil, Eucalyptusficifolia (red flowering gum), eucalyptus flower, Eucalyptusfructicetorum F. Von Mueller, eucalyptus globules tree, Eucalyptusglobulus Labillardiere, Eucalyptusgunnii (cider gum), Eucalyptusjohnstonii (yellow gum), eucalyptus leaf extract, Eucalyptusleucoxylon (white ironbark), Eucalyptusmaculate, Eucalyptusoccidentalis, Eucalyptusparvifolia, Eucalyptuspauciflora subsp. niphophila (snow gum), Eucalyptusperriniana (spinning gum), eucalyptus pollen, Eucalyptussideroxylon (red ironbark), Eucalyptussmithii R.T. Baker, Eucalyptusurnigera (urn gum), Eucalyptusviminalis Labill (euvimals), Eucalyptus polybractea, Eucalyptus spp., eucalytpo setma ag, fevertree, gommier bleu, gum tree, kafur ag, lemon eucalyptus extract, lemon-scented gum, malee, Meijer® (eucalyptus oil, camphor, menthol), mountain gum, myrtaceae, oil of eucalyptus citriodora, oleum eucalypti, red flowering gum, red gum, red ironbark, schonmutz, snow gum, southern blue gum, spinning gum, stringy bark tree, Tasmanian blue gum, Tasmanian snow gum, urn gum, verbenone, white ironbark, yellow gum.

evidence table

These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.
Arthritis (Grade: C)
Aromatherapy using eucalyptus has been studied for its effects on pain, depression, and feelings of satisfaction in life in arthritis patients. Aromatherapy may help reduce pain and depression, but does not appear to alter the feeling of satisfaction in life. Additional study is needed to clarify these findings.
Asthma (Grade: C)
Further research is needed to confirm anti-inflammatory and mucolytic activity before this agent can be recommended in upper and lower airway diseases.
Decongestant/expectorant (Grade: C)
Although commonly used in non-prescription products, there is inconclusive scientific study of eucalyptus oil or eucalyptol. Better research is necessary before a recommendation can be made.
Dental plaque/gingivitis (mouthwash) (Grade: C)
Although studies on combination mouthwashes show effectiveness (such as Listerine®), it is not clear that eucalyptus oil by itself is effective or safe for this purpose.
Headache (applied to the skin) (Grade: C)
Effectiveness of eucalyptus oil applied to the skin for headache relief has not been supported with reliable human research.
Skin ulcers (Grade: C)
Limited evidence suggests that eucalyptus essential oil may be beneficial for patients with skin ulcers when combined with antibiotics. More studies are needed to confirm these early findings.
Smoking cessation (Grade: C)
Nicobrevin is a proprietary product marketed as an aid for smoking cessation that contains quinine, menthyl valerate, camphor, and eucalyptus oil. Despite use of this product, there is a lack of evidence suggesting benefit of this product or eucalyptus oil for smoking cessation.
Tick repellant (topical) (Grade: C)
Preliminary research shows that Citriodiol® spray, containing eucalyptus, may reduce the number of tick bites and thereby tick-borne infections, although additional studies are warranted.