Overview:

Eucalyptus (Eucalyptus globulus) is a tall evergreen tree native to Australia and Tasmania. Today, most commercial herbal preparations originate in Mediterranean and subtropical regions, including Spain and Morocco. The leaves and oil of the eucalyptus plant are used for medicinal purposes. Eucalyptus oil consists of the volatile oil distilled from the fresh leaves and branch tops of the eucalyptus plant.

Topical ointments containing eucalyptus oil have been used in traditional Aboriginal medicines to heal wounds and fungal infections. Teas containing eucalyptus leaves were also used to reduce fevers. The therapeutic uses of eucalyptus soon spread to other traditional medicine systems, including Chinese, Indian (Ayurvedic), and Greco-European.

Throughout the 19th century in England, eucalyptus oil was used in hospitals to clean urinary catheters. Laboratory studies later revealed that eucalyptus oil contains substances with strong antibacterial properties. Studies in animals and test tubes also found that eucalyptus oil acts as an expectorant (loosens phlegm in the respiratory passages), antiseptic (prevents infection), and deodorant. Like eucalyptus oil, the leaves of the eucalyptus plant contain substances that have expectorant, antibacterial, and antiseptic properties, but the leaves are also believed to help reduce inflammation and reduce fevers. In fact, one study conducted in Russia found that an alcoholic extract containing eucalyptus leaves helps relieve chronic ear infections. Many researchers believe that the beneficial effect of the eucalyptus tincture may have been due to its anti-inflammatory properties.

Plant Description:

There are many species of eucalyptus. Some are the size of an ornamental shrub, and some grow to be giant trees. The type of eucalyptus that is most often used medicinally is called blue gum or Australian fever tree. It can grow as high as 230 feet. Its 4 - 12 inch leaves are dark green and shiny. Its blue-gray bark peels to reveal a cream-colored inner bark.

Medicinal Uses and Indications:

Eucalyptus has been used traditionally to treat diabetes, and a few animal studies suggest that this folkloric use has scientific merit. Mice with experimentally-induced diabetes respond to aqueous extracts of eucalyptus by increasing insulin production and reducing blood sugar. These results suggest that eucalyptus may be useful as an adjunctive treatment for diabetes. More research is needed.

Today, eucalyptus is commonly used in remedies to treat coughs and the common cold. It can be found in many lozenges, cough syrups, rubs, and vapor baths throughout the United States and Europe. Herbalists recommend the use of fresh leaves in teas and gargles to soothe sore throats and treat bronchitis and sinusitis.

Ointments containing eucalyptus leaves are also applied to the nose and chest to relieve congestion. Eucalyptus oil helps loosen phlegm, so many health care providers recommend inhaling eucalyptus vapors to help treat bronchitis, coughs, and the flu.On the skin, eucalyptus oil has been used to treat arthritis, boils, sores and wounds. The oil can also be rubbed on the skin as an insect repellent.

Because eucalyptus has such a sharp, pungent aroma, some aromatherapists recommend using it like smelling salts to revive someone who has fainted. Generally, most aromatherapists suggest placing a drop or two of eucalyptus oil on a cloth and holding it under the nose of the individual who has fainted. Eucalyptus oil is also rich in cineole (a potent antiseptic that kills bacteria responsible for bad breath), so some professional herbalists may also recommend diluted eucalyptus tinctures to treat bad breath.

What's It Made Of?:

Eucalyptus leaves contain tannins (which are believed to help reduce inflammation), flavonoids (such as quercetin, which has antioxidant properties), and volatile oils.

Eucalyptus oil is a rich source of the antiseptic substance cineole (sometimes referred to as eucalyptol).

Available Forms:

Eucalyptus oil is available in many products, including liquids and ointments. The leaves of the eucalyptus plant are available fresh, dried (to be used in teas), and in liquid extracts (solution made from herb and alcohol or herb, alcohol, and water). Commercial cough drops, syrups, vaporizer fluids, liniments, toothpastes, and mouthwashes may contain eucalyptus oil or its active ingredient, cineole. Some of the familiar over-the-counter remedies that contain eucalyptus oil include Listerine, Mentholatum Cherry Chest Rub, and Vicks VapoRub.

How to Take It:

Pediatric

Children should not ingest eucalyptus leaves or oil. Only children older than 6 years of age should take cough drops containing eucalyptus.

Use of eucalyptus as steam, salve, or chest rub may be appropriate for children. The doses for these uses are similar to those for adults (see below). Eucalyptus oil should not be applied to the face or nose of children under age 2.

Adult

• Eucalyptus leaf as infusion (tea): 1/4 - 1/2 teaspoonful per cup hot water, 3 times daily. Steep for 10 - 15 minutes, and drink as recommended.
• Eucalyptus leaf tincture (for congestion): 10 - 30 drops daily
• Eucalyptol: 0.05 - 0.2 mL (1 - 2 drops per cup boiling water) daily
• Eucalyptus oil (for topical application): add ½ - 1 mL (15 - 30 drops) of oil to 1/2 cup of carrier oil (sesame, almond, olive, etc.). For inhalation, add 5 - 10 drops of oil to 2 cups boiling water. Place towel over head and inhale steam.

Precautions:

The use of herbs is a time-honored approach to strengthening the body and treating disease. Herbs, however, contain components that can trigger side effects and that can interact with other herbs, supplements, or medications. For these reasons, herbs should be taken with care, under the supervision of a health care provider qualified in the field of botanical medicine.

Individuals with inflammation of the kidneys or gastrointestinal tract, bile duct inflammatory disease, liver disease, or low or high blood pressure should not use eucalyptus leaf extract. Tannins in the leaves may cause stomach upset or kidney and liver damage if leaf preparations are ingested in large amounts.

People with asthma should use eucalyptus oil with caution due to the herbs potential to tigger an asthma attack.

Pregnant and breastfeeding women should not use eucalyptus.

When used externally, eucalyptus oil is nontoxic. When taken internally, however, eucalyptus oil is toxic and must be diluted.

Possible Interactions:

If you are currently being treated with any of the following medications, you should not use eucalyptus without first talking to your health care provider.

• 5-Fluorouracil (5-FU) -- In an animal study, topical eucalyptus oil enhanced the absorption of topical 5-fluorouracil (5-FU), a medication used to treat cancer.
• Other Possible Interactions -- Eucalyptus may increase how quickly the body eliminates some medications, including pentobarbital, a barbiturate used as an anesthetic, and amphetamine, a stimulant used for narcolepsy and attention deficit hyperactivity disorder.

Alternative Names:

Australian fever tree; Blue gum; Eucalyptus globulus; Red gum