What Is It?
Guidelines for Use
Possible Side Effects
Evidenced Based Rating Scale
From cough cure to tension-reliever, the woody scented oil and leathery leaves of the stately eucalyptus tree have found myriad uses over the centuries. Australian aborigines relied on this native evergreen for soothing painful joints and healing skin lesions. Settlers to the continent dubbed Eucalyptus the "fever tree" in recognition of its disease-fighting powers. While these early users ascribed its potency to the tree's brisk aroma, it is now known that the thirsty roots were also helpful: they kept the surrounding ground relatively dry and thus free of malaria-carrying mosquitoes.
Once Europeans were introduced to the Eucalyptus tree, they also rapidly recognized its gifts—medicinal and otherwise. In fact, they began to rely so heavily on Eucalyptus oil for sterilizing medical and surgical equipment that it was briefly referred to as "catheter oil."
Of the 300 Eucalyptus species, the most commonly used medicinally are Eucalyptus globulus and E. fructicetorum. The crucial medicinal compound called eucalyptol (also known as cineole) appears in the oil, which is steam-extracted from the leaves and branch tips of these species. Oils of industrial- and perfume-grade quality are typically taken from altogether different Eucalyptus species.
One of the most enduring medical uses for Eucalyptus and, not surprisingly, one of the best substantiated is its power to ease nasal congestion and quell cough. In fact, many commercial cough and cold remedies feature small amounts of the potent oil, as do countless chest rubs and pain-relieving lotions. Because it's so strong, the oil is typically diluted before being placed in these products.
Many uses for Eucalyptus have been proposed and tested over the years. One study found that a blend of Eucalyptus oil, peppermint oil, and ethanol could relieve headache-related muscle tension and had a mentally relaxing effect when it was gently rubbed into the forehead and temples. (1) Other research indicates that Eucalyptus oil can kill dust mites and fleas—common sources of allergic reactions. (2, 3) The oil is also a natural flea, gnat and mosquito repellent. (4)
Specifically, Eucalyptus may help to:
Clear congestion and relieve cough associated with colds, flu, asthma, and sinusitis; and relieve cough from croup. When inhaled, eucalyptol, the oil's key medicinal ingredient, works as an expectorant, loosening sticky Mucus and making it easier to cough up and out of the chest. (5) In addition, astringent substances in the oil called tannins shrink and soothe, swollen and inflamed Mucous membranes in the mouth, nose, and throat. (6, 7) Lozenges containing eucalyptol increase saliva production, prompting more frequent swallowing, thus, reducing the impulse to cough. And the oil's germ-fighting actions may reduce the risk of a secondary respiratory infection. A 2006 laboratory study of 200 samples collected from patients with respiratory tract disorders indicated potential antibacterial affects of Eucalyptus globulus leaf Extract. (8)
The anti-inflammatory, anti-spasmodic and mucolytic properties of Eucalyptus oil may be particularly important in treating patients with asthma. (5-7, 9) Preliminary research indicates that when Eucalyptus oil is taken orally or its vapors are inhaled, it may reduce asthma symptoms enough to allow for a reduction in the dosage of conventional oral steroids in patients with severe asthma. In a 2003 study, 32 steroid-dependent patients with asthma received either 200 mg of eucalyptol or Placebo capsule daily for two months. In the treatment group, 75% of patients reduced daily prednisolone dosage by an average 36%, while 25% of patients in the placebo group reduced steroid usage by only 7%. (10) More research is needed.
Control earache pain. Inflammation or infection inside the ear can lead to an earache resulting from pressure in the middle ear that causes pain and may also interfere with hearing. Earaches are frequently the result of fluids backing up in the Eustachian tube – the channel between the middle ear and the back of the throat—and settling into the middle ear. The inflammation associated with allergies and upper respiratory infections, such as colds, can also cause swelling around the Eustachian tube that blocks drainage. The mucolytic and anti-inflammatory properties of Eucalyptus are important in relieving the congestion that can lead to an earache. When inhaled, a steam solution containing Eucalyptus oil will prompt the Eustachian tubes connecting the middle ear and the throat to open. Fluids will more easily drain from the ear as a result, relieving often-painful pressure. (11-13)
Treat cuts and scrapes and other minor wounds. In test tube studies, Eucalyptus oil has been shown to fight infection-causing bacteria, fungi, and viruses. (8, 14-15) This antiseptic action, as well as its anti-inflammatory powers, helps explain the oil's popularity for treating wounds in the pre-Antibiotic era. More research is needed to confirm the use of Eucalyptus for these uses today.
Ease arthritis pain and muscle aches. Rubbed into the skin, Eucalyptus oil (diluted with carrier oil such as sunflower or sweet almond oil) seems to stimulate blood flow and generate a feeling of warmth. Its most important function may be to distract, or mask, underlying discomfort or pain, making it useful for those suffering from arthritis or muscle aches. However, research is lacking in this area. Preliminary evidence indicates that aromatherapy with Eucalyptus may be effective in treating arthritis. A study of 40 patients with rheumatoid arthritis found that the essential oils of Eucalyptus, lavender, marjoram, rosemary and peppermint helped to reduce pain and depression associated with arthritis. However, the article is written in Korean, and it is unclear whether the oil mixture was applied topically or whether the vapors were inhaled and which component may have been responsible for the effects. (16)
Fight gum disease. Most likely because of its germ-fighting properties, Eucalyptus appears to inhibit the formation of the sticky film on teeth and gums known as plaque. If allowed to build up over time, plaque will turn into a hard Mineral shell called tartar that wears away at gum tissue. Several studies have shown that chewing gum containing Eucalyptus is more effective than a Placebo in stopping plaque from forming. (17-18) However, some conflicting evidence exists. (19) In a 2009 study of 30 patients with gingivitis and plaque, a toothpaste containing Eucalyptus was no more effective than conventional toothpaste in controlling the condition. (20)
Note: Eucalyptus has also been found to be useful for a number of other disorders. For information on these additional ailments, see our Dosage Recommendations Chart for Eucalyptus.
- Not all Eucalyptus species provide the medically therapeutic oil; look for products containing at least 70% to 85% eucalyptol (cineole).
- Eucalyptus oil should always be diluted before applying it topically or ingesting it; always follow package instructions.
- For earache and for cough and congestion related to colds, flu, asthma, sinusitis, and other types of respiratory conditions, there are three effective treatment approaches:
--Make a steam inhalation solution. Add a drop of Eucalyptus oil (or two or three leaves) to a pan of water. Bring the water to a boil and remove the pan from the heat. Drape a towel over your head and the pan. Close your mouth and inhale the steam deeply through both nostrils. Blow your nose as frequently as necessary. Repeat twice daily, more frequently for earaches.
--Add a drop or two of Eucalyptus oil to a commercial steam inhaler. Follow the manufacturer's instructions.
--Drink two cups of Eucalyptus leaf Infusion daily. Make the infusion by pouring one cup (8 ounces) of hot (but not boiling) water over 1 to 2 teaspoons of finely crushed Eucalyptus leaves. Steep for 10 minutes, then strain. Alternatively, make the infusion with Eucalyptus tincture, adding the number of drops designated on the label (typically 30 to 45) to an 8-ounce cup of hot water.
For minor wounds: Clean the wound thoroughly. Mix the diluted Eucalyptus oil with an equal quantity of an alcohol-based topical antiseptic and apply a few drops to the affected area. Seek medical attention if signs of infection develop (redness, localized warmth, fever).
For arthritis pain or muscle aches: Rub several drops of well-diluted Eucalyptus oil into the skin. Alternatively, soak in an herbal bath made by wrapping a handful of Eucalyptus leaves in cheesecloth and allowing the bath water to run through the bundle.
For gum disease: Place a few drops of well-diluted Eucalyptus oil onto the fingertip and massage into the gums. Alternatively, purchase toothpaste containing Eucalyptus oil.
Be sure to check out the Dosage Recommendations Chart for Eucalyptus, which lists therapeutic dosages for specific ailments at a glance.
Guidelines for Use
Protect eyes from the oil's strong fumes by keeping them shut when inhaling any Eucalyptus remedy.
There are no known drug or nutrient interactions associated with Eucalyptus leaf or oil.
Possible Side Effects
In rare cases, Eucalyptus can cause nausea, vomiting, and diarrhea. Consult a doctor if this occurs.
In the small number of people who are allergic to Eucalyptus, a topical preparation containing the oil may cause an irritating but relatively harmless rash while applying it to the face. Inhaling Eucalyptus preparations can worsen a runny nose and watery eyes, and make asthma worse.
Ingesting even small amounts of undiluted Eucalyptus oil can cause serious reactions, including a drop in blood pressure, circulation problems, collapse, suffocation, and death. Commercial products that contain the oil pose this risk as well if ingested in higher-than-recommended amounts. Seek emergency medical care if an overdose is suspected.
- When used as recommended, Eucalyptus-containing commercial preparations, including Eucalyptus tea, are very safe. Still, it's important to handle Eucalyptus oil with extreme care.
- Because of its potency, don't administer any product containing Eucalyptus (internal or external) to a small child.
- Eucalyptus oil products should never be applied to the face of an infant or small child -- especially on or near the nose -- because they can cause asthma-like reactions. Extreme cases could potentially result in death by asphyxiation.
- Don’t take Eucalyptus if you have digestive problems, inflammation of the stomach or intestines, a bile (gall bladder) duct disorder, or liver disease. The tannins in the leaves can irritate these conditions and may cause further damage.
- Pregnant women should not take Eucalyptus.
1. Göbel H, Schmidt G, Soyka D. Effect of peppermint and eucalyptus oil preparations on neurophysiological and experimental algesimetric headache parameters. Cephalalgia. 1994 Jun;14(3):228-34.
2. Tovey ER, McDonald LG. Clinical aspects of allergic disease: A simple washing procedure with eucalyptus oil for controlling house dust mites and their allergens in clothing and bedding. J Allergy Clin Immunol. 1997;100:464-7.
3. Saad el-Z, Hussien R, Saher F, Ahmed Z. Acaricidal activities of some essential oils and their monoterpenoidal constituents against house dust mite, Dermatophagoides pteronyssinus (Acari: Pyroglyphidae). J Zhejiang Univ Sci B. 2006 Dec;7(12):957-62.
4. U.S. Environmental Protection Agency. p-Menthane-3,8-diol (011550) Fact Sheet. Available at http://www.epa.gov/oppbppd1/biopesticides/ingredients/factsheets/factsheet_011550.htm. Accessed July 21, 2010.
5. Sinclair, A. Remedies for common family ailments: 10. Nasal decongestants. Prof Care Mother Child. 1996;6(1):9-11.
6. Silva J, Abebe W, Sousa SM, Duarte VG, Machado MI, Matos FJ. Analgesic and anti-inflammatory effects of essential oils of Eucalyptus. J Ethnopharmacol. 2003 Dec;89(2-3):277-83.
7. Vigo E, Cepeda A, Gualillo O, Perez-Fernandez R. In-vitro anti-inflammatory effect of Eucalyptus globulus and Thymus vulgaris: nitric oxide inhibition in J774A.1 murine macrophages. J Pharm Pharmacol 2004;56:257-63.
8. Salari MH, Amine G, Shirazi MH, Hafezi R, Mohammadypour M. Antibacterial effects of Eucalyptus globulus leaf extract on pathogenic bacteria isolated from specimens of patients with respiratory tract disorders. Clin Microbiol Infect. 2006 Feb;12(2):194-6.
9. Sadlon AE, Lamson DW. Immune-modifying and antimicrobial effects of eucalyptus oil and simple inhalation devices. Altern Med Rev. 2010 Mar;15(1):33-47.
10. Juergens UR, Dethlefsen U, Steinkamp G, et al. Anti-inflammatory activity of 1.8-cineol (eucalyptol) in bronchial asthma: a double-blind placebo-controlled trial. Respir Med 2003;97:250-6.
11. Newall CA, Anderson LA, Phillipson JD. Herbal Medicines: A Guide for Health Care Professionals. London, England: The Pharmaceutical Press; 1996:72-73.
12. Herbs2000. Earache. http://www.herbs2000.com/disorders/earache.htm. Accessed July 19, 2010.
13. DigHerbs. Ear Ache Herbal Remedies. http://www.digherbs.com/ear-ache.html. Accessed July 19, 2010.
14. Takahashi T, Kokubo R, Sakaino M. Antimicrobial activities of eucalyptus leaf extracts and flavonoids from Eucalyptus maculata. Lett Appl Microbiol 2004;39:60-4.
15. Al-Saimary IE, Bakr SS, Jaffar T, et al. Effects of some plant extracts and antibiotics on Pseudomonas aeruginosa isolated from various burn cases. Saudi Med J. 2002 Jul;23(7):802-5.
16. Kim MJ, Nam ES, Paik SI. The effects of aromatherapy on pain, depression, and life satisfaction of arthritis patients. Taehan Kanho Hakhoe Chi 2005 Feb;35(1):186-94.
17. Adámková H, Vicar J, Palasová J, Ulrichová J, Simánek V. Macleya cordata and Prunella vulgaris in oral hygiene products – their efficacy in the control of gingivitis. Biomed Pap Med Fac Univ Palacky Olomouc Czech Repub. 2004 Jul;148(1):103-5.
18. Nagata H, Inagaki Y, Tanaka M, et al. Effect of eucalyptus extract chewing gum on periodontal health: a double-masked, randomized trial. J Periodontol. 2008 Aug;79(8):1378-85.
19. Charles CH, Vincent JW, Borycheski L, et al. Effect of an essential oil-containing dentifrice on dental plaque microbial composition. Am J Dent. 2000 Sep;13(Spec No):26C-30C.
20. George J, Hegde S, Rajesh KS, Kumar A. The efficacy of a herbal-based toothpaste in the control of plaque and gingivitis: a clinico-biochemical study. Indian J Dent Res. 2009 Oct-Dec;20(4):480-2.
Evidence Based Rating Scale
The Evidence Based Rating Scale is a tool that helps consumers translate the findings of medical research studies and what our clinical advisors have found to be efficacious in their personal practice into a visual and easy to interpret format. This tool is meant to simplify the information on supplements and therapies that demonstrate promise in the treatment of certain conditions.
Preliminary evidence indicates benefit in a mixture with other essential oils, but form of administration was not adequately described. (16)
Long history of use and preliminary evidence indicates efficacy as anti-inflammatory and anti-spasmodic. (5-7, 9-10)
Long history of use and preliminary evidence indicates efficacy as astringent, expectorant and anti-inflammatory. (5-8)
Long history of use and preliminary evidence indicates antibacterial, anti-inflammatory and expectorant effects. (5-10)
|Cuts and Scrapes
Preliminary laboratory studies indicate antiseptic properties effective in wound healing. (8, 14-15)
Long history of use and preliminary evidence indicates efficacy as expectorant. (11-13)
Long history of use and preliminary evidence indicates antibacterial, anti-inflammatory and expectorant effects. (5-10)
Several studies indicate efficacy in preventing plaque build-up. Conflicting evidence indicates no more efficacious than conventional toothpaste for existing plaque and gingivitis. More study is needed. (17-20)
Long history of use and preliminary research indicates strong antibacterial properties. (5-8)