Eucalyptus

The eucalyptus tree is a large, fast-growing evergreen that is native to Australia and Tasmania. The tree can grow to 375-480 feet (125-160 meters). Eucalyptus belongs to the myrtle (Myrtaceae) family. There are more than 300 species of eucalyptus, and Eucalyptus globulus is the most well-known species. One species (E. amygdalin) is the tallest tree known in the world. The tree grows best in areas with an average temperature of 60°F (15°C).

Eucalyptus trees constitute over 75% of the tree population of Australia. The eucalyptus tree is also known in Australia as the blue gum tree or malee. Other names for eucalyptus include Australian fever tree and stringy bark tree. The name is actually derived from the Greek word “eucalyptos,” which means “well covered,” and refers to the cuplike membrane that covers the budding flowers of the tree.

The bluish green leaves carry the medicinal properties of the tree and grow to a length of 6-12 inches (15- 30 cm). While the leathery leaves are the sole food for koala bears, the leaves also contain a fragrant volatile oil that has antiseptic, expectorant, antibacterial, anti-inflammatory, deodorant, diuretic, and antispasmodic properties. Other constituents of the leaves include tannins, phenolic acids, flavonoids (eucalyptin, hyperin, hyperoside, quercitin, quercitrin, rutin), sesquiterpenes, aldehydes, and ketones.


Eucalyptus oil is obtained through a steam distillation process that removes the oil from the fresh, mature leaves and branch tips of older trees. Approximately 25 species of eucalyptus trees in Australia are grown for their oil.

There are three grades of eucalyptus oil: medicinal, which contains the compound eucalyptol (also called cineol); industrial, in which a component of the oil is used in mining operations; and aromatic, which is used in perfumes and fragrant soap products. These oils vary greatly in character.

When choosing an oil for therapeutic use, it is important to know from what species the oil was derived. Species used medicinally include E. globulus, which contains up to 70% eucalyptol; E. polybractea, which contains 85% eucalyptol; and E. Smithii. Eucalpytus amygdalina and E. dives contain little eucalyptol and are used to separate metallic sulfides from ores in the mining industry. Eucalyptus citriodora contains a lemon-scented oil and is an ingredient in perfumes, as is E. odorata and E. Sturtiana. Two species, E. dives and E. radiata, have oils with a strong peppermint odor.

The most common species grown for its medicinal oil is Eucalyptus globulus. The eucalyptol found in this species is a chief ingredient in many over-the-counter cold and cough remedies, such as cough lozenges, chest rubs, and decongestants. It acts to stimulate blood flow and protects against infection and germs. The British Pharmocopoeia requires that commercial eucalyptus oils contain 55% eucalyptol by volume.

Origins

The Australian aborigines have used eucalyptus for hundreds of years as a remedy for fever, wounds, coughs, asthma, and joint pain. Australian settlers named the eucalyptus the fever tree because of its disease- fighting properties. Baron Ferdinand von Miller, a German botanist and explorer, was responsible for making the properties of eucalyptus known to the world in the mid-1800s.

Likening eucalyptus’ scent to that of cajaput oil (a disinfectant), von Miller suggested that eucalyptus might also be used as a disinfectant in fever districts. Seeds of the tree were sent to Algiers, France and planted. The trees thrived and, because of the drying action of the roots, turned one of the marshiest areas of Algiers into a dry and healthy environment, thereby driving away malaria-carrying mosquitoes.

Eucalyptus trees were then planted in temperate areas around the world to prevent malaria. As a result, eucalyptus trees are now cultivated in China, India, Portugal, Spain, Egypt, South and North Africa, Algeria, South America, and in the southern portion of the United States.


Commercial production of eucalyptus began in Victoria, Australia in 1860. The nineteenth century eclectic doctors adopted eucalyptus as a treatment for fevers, laryngitis, asthma, chronic bronchitis, whooping cough, gonorrhea, ulcers, gangrenous tissue, edema, and gastrointestinal disturbances. European doctors used eucalyptus oil to sterilize their surgical and medical equipment. Eucalyptus leaves were often made into cigars or cigarettes and smoked to relieve asthma and bronchial congestion.

Modern medicines around the world have included eucalyptus in their practices. Indian ayurvedics use eucalyptus to treat headaches resulting from colds. Eucalyptus is listed in the Indian Pharmacopoeia as an expectorant and in the Chinese Pharmacopoeia as a skin irritant used in nerve pain.

In France, eucalyptus leaves are applied topically to relieve congestion from colds and to treat acute bronchial disease. A standardized eucalyptus tea is licensed in Germany to treat bronchitis and throat inflammations. Eucalyptus is also an ingredient in German herbal cough preparations. The German Commission E has approved the internal use of eucalyptus to treat congestion of the respiratory tract, and the external use to treat rheumatic complaints.

In the United States, eucalyptus is a component of many decongestant and expectorating cough and cold remedies, such as cough drops, cough syrups, and vapor baths. Eucalyptus is often used in veterinary medicine. It is used to treat horses with flu, dogs with distemper, and to treat parasitic skin conditions.

General use 

Eucalyptus is most popular for its ability to clear congestion due to colds, coughs, flu, asthma, and sinusitis. The tannins found in eucalyptus have astringent properties that reduce mucous membrane inflammation of the upper respiratory tract. Eucalyptol, the chemical component of the oil, works to loosen phlegm.

Cough drops containing eucalyptus promote saliva production, which increases swallowing and lessens the coughing impulse. Earaches can also be treated with eucalyptus. When inhaled, the eucalyptus fumes open the eustachian tubes, draining fluids and relieving pressure. Eucalyptus enhances breathing, which makes it an effective remedy for asthma, bronchitis, sinusitis, whooping cough, and colds.

Eucalyptus is a component of many topical arthritis creams and analgesic ointments. When applied to the skin, eucalyptus stimulates blood flow and creates a warm feeling to the area, relieving pain in muscles and joints.

The oil extracted from the eucalyptus leaf has powerful antiseptic, deodorizing, and antibacterial properties. It is especially effective in killing several strains of Staphylococcus bacteria. A mixture of 2% eucalyptus oil evaporated in an aroma lamp has been shown to destroy 70% of the Staphylococcus bacteria in the affected room.

When the oil is applied to cuts, scrapes, and other minor wounds, it inhibits infections and viruses. A 2002 report out of Australia made researchers around the world take note when two cases of patients with staph infections resistant to traditional antibiotic therapy responded to a mixture of eucalyptus leaf oil abstract. The Australian researchers recommended formal clinical trials to test the therapy, based on an ancient aboriginal remedy. Eucalyptus also fights plaque-forming bacteria and is used to treat gum disease and gingivitis.

In large doses, the oil can be a kidney irritant and can induce excretion of bodily fluids and waste products. Eucalyptus oil added to water may be gargled to relieve sore throat pain or used as a mouthwash to heal mouth sores or gum disorders. Consequently, eucalyptus is an ingredient in many commercial mouthwashes.

Eucalyptus’ pain-relieving properties make it a good remedy for muscle tension. One study showed that a mixture of eucalyptus, peppermint, and ethanol oils successfully relieved headache-related muscle tension.

Eucalyptus may lower blood sugar levels. Placing a drop of the oil on the tongue may reduce nausea. The oil has also been used to kill dust mites and fleas.

Eucalyptus oil is one of the most well-known fragrances in aromatherapy. Two species of eucalyptus are used in aromatherapy oils: E. globulus and E. citriodora. The essential oil of eucalyptus is used to relieve cramps, cleanse the blood, heal wounds, disinfect the air, and to treat conditions such as asthma, bronchitis, throat and sinus infections, fevers, kidney infections, rheumatism, bladder infections, and sore muscles.

The essential oil can be diluted and added to a massage oil to ease aching muscles. The oil can be added to hot water and inhaled to reduce nasal congestion. It can also be diffused in the room of a sick patient to disinfect the air.

Some believe that inhaling the diffused oil can enhance concentration and thought processes. Studies have shown that inhalation of the cineole compound of eucalyptus stimulates coordination and motor activities in mice. Eucalyptus oil may also uplift the spirit during times of emotional overload or general sluggishness.

Applying a diluted oil to the skin instead of inhaling it increases the rate of absorption into the blood. Often the speed with which it is absorbed is so fast, the odor can be detected on the breath within minutes.

The oil is also an effective febrifuge, and a cold compress with eucalyptus oil added to it has a cooling effect that is useful in helping to reduce a fever. The essential oil of eucalyptus is also used to treat wounds, herpes simplex virus, skin ulcers, and acne. Combined with water, the oil makes an effective insect repellant. Because of its skin-moistening properties, the oil is often an ingredient in dandruff shampoo.

Eucalyptus oil may be combined with other oils that have similar properties, such as niaouli, pine, Swiss pine, hyssop, and thyme oils. It also mixes well with lemon, verbena, balm, and lavender oils.

Preparations

Eucalyptus is available as a tincture, cream, ointment, essential oil, or lozenge. Many health food stores carry fresh or dried eucalyptus leaf in bulk. Eucalyptus can be ingested through the use of teas or tincture preparations, inhaled, or applied externally.

Eucalyptus infusion is ingested to treat coughs, colds, bronchitis, congestion, and throat infections. To create an infusion, 1 cup of boiling water is poured over 1-2 teaspoons of crushed eucalyptus leaves. The mixture is covered and steeped for 10 minutes and is then strained. Up to 2 cups can be drunk daily.

Inhaling eucalyptus vapors is beneficial for sinus and bronchial congestion that occurs with bronchitis, whooping cough, colds, asthma, influenza, and other respiratory illnesses. A drop of eucalyptus oil or two to three fresh or dried leaves are added to a pan of boiling water or to a commercial vaporizer. The pan is removed from the heat, a towel is placed over the pan and the patient’s head, and the patient inhales the rising steam. Patients should close their eyes when inhaling the steam to protect them from eucalyptus’ strong fumes.

For healing wounds and preventing infection, the wound is washed and then diluted eucalyptus oil or crushed eucalyptus leaves are applied to the affected area.

For relief of muscle aches or arthritis pain, several drops of the diluted oil are rubbed onto the affected area, or a few drops of diluted oil are added to bath water for a healing bath. Adding eucalyptus leaves wrapped in a cloth to running bath water is also effective.

For gum disease, a few drops of diluted oil are placed on a fingertip and massaged into the gums.

Tinctures should contain 5-10% essential oil of eucalyptus. A person can take 1 ml three times daily.

Ointments should contain 5-20% essential oil of eucalyptus. The person should use as directed for chapped hands, joint and muscle pains, and dandruff.

Precautions

Children or infants should not be treated with eucalyptus. Of special note, eucalyptus oil should not be applied to the facial areas (especially the nose or eyes) of small children or infants. Pregnant or breast-feeding women should not use eucalyptus.

People with digestive problems, stomach or intestinal inflammations, biliary duct disorders, or liver disease should not take eucalyptus.

Undiluted eucalyptus oil should never be ingested. Small amounts of undiluted oil (even in amounts as little as one teaspoon) are toxic and may cause circulatory problems, collapse, suffocation, or death. Eucalyptus oil should always be diluted in a carrier oil such as almond, grapeseed, or other vegetable oil before applying to the skin.

Side effects

Nausea, vomiting, or diarrhea may occur in rare cases. Applying eucalyptus to the skin may cause a rash in those who are sensitive or allergic to eucalyptus.

Interactions

Eucalyptus works to detoxify the body. If it is used simultaneously with other drugs, the effects of those drugs may be weakened.

Eucommia bark

Eucommmia bark is the gray, grooved bark of the tree Eucommia ulmoides, commonly called the hardy rubber tree or the gutta-percha tree. The Chinese name for eucommia bark is Du Zhong. This name refers to a Taoist monk who was said to be immortal, suggesting that the herb provides long life, good health, and vitality.

The tree is a member of the rubber family and is native to the mountainous regions of China. It normally grows to about 50 ft (15 m) in height. Small patches of bark are harvested from trees over 10 years old in late summer and early autumn. The outer bark is peeled away and the smooth inner bark is dried. This inner bark contains a pure white, elastic latex that is thought to contain the compounds that account for eucommia bark’s healing properties. Older, thicker inner bark with more latex is considered more desirable for the herbalist to use than younger, thinner bark.

Although traditionally only the bark of E. ulmoides was used for healing, research in the later half of the 1990s in Japan indicates that the leaves also have healing properties. The green leaves are shiny, narrow, and pointed. The tree’s flowers are very small and are not used in healing.


General use

Eucommia bark has been used in traditional Chinese herbalism for over 3,000 years. Since the tree does not grow widely outside China, this herb was not used in other cultures until recently.

Eucommia bark is strongly associated with the kidneys and to a lesser extent with the liver. In Chinese medicine, the kidneys store jing. Jing is an essential life source and associated with whole body growth and development, as well as normal sexual and reproductive functioning. The kidney and liver jing also affects the bones, ligaments, and tendons.

In the Chinese system of health, yin aspects must be kept in balance with yang aspects. Ill health occurs when the energies and elements of the body are out of balance or in disharmony. Health is restored by taking herbs and treatments that restore that balance.

Eucommia bark is the primary herb used to increase yang functions in the body. However, it also supports yin functions. Eucommia bark helps to build strong bones and a flexible skeleton with strong ligaments and tendons. It is a primary herb used to heal tissues that are slow to mend after an injury or that have weakened through stress or age.

It is given to treat lower back and leg pain, stiffness, arthritis, and knee problems including continual dislocation. Eucommia bark is also believed to have diuretic properties that aid in reducing swelling. Although it can be used alone, eucommia bark is most often used in conjunction with other herbs that support its functions.

In addition to healing tissues, eucommia bark has two other major functions. In pregnant women it is given to calm the fetus, soothe the uterus, and prevent miscarriage. Eucommia bark also has the ability to reduce blood pressure. This property has been investigated since 1974, and may be related to its mild diuretic action. Eucommia bark is used in almost all Chinese formulas to lower blood pressure.

Other modern uses of eucommia bark include treatment of impotence, premature ejaculation, and as a mild anti-inflammatory. It is included in tonics that boost the immune system and generally improve wellness. However, there is little rigorous scientific research to support these uses.


In the late 1990s Japanese researchers became interested in eucommia bark. In 2000, researchers at Nihon University in Chiba, Japan, published two studies showing that both the leaves and the bark of Eucommia ulmoides contained a compound that encourages the development of collagen in rats.

Collagen is an important part of connective tissues such as tendons and ligaments. However, they found that the compound was present in much greater quantities in fresh leaves and fresh bark, and that much of it was destroyed during the drying process.

In modern Japan, eucommia leaves are also believed to help with weight loss by reducing the urge to eat. For this reason, in the late 1990s eucommia leaves became an increasingly popular herb there. However, there are no scientific studies to support this function of the herb.

Preparations

Eucommia bark is harvested and dried. Before boiling, it is sliced to expose the inside of the bark. The bark is then boiled to make a decoction. Generally this decoction is combined with other herbs and extracts to create yang enhancing tonics to treat kidney and liver deficiencies and impotence.

Precautions

Eucommia bark has a long history of use with no substantial reported problems.

Side effects

No side effects have been reported with the use of eucommia bark.

Evening primrose oil

Evening primrose (Oenothera biennis) is a tall, hardy, native biennial of the Onagraceae family. Its Latin name is derived from the Greek word oinos for wine and thera for hunt and reflects the folk belief that the herb could minimize the ill effect of over-indulgence in wine following a hunt.

The plant thrives in dry, sunny meadows, and is abundant in many parts of the world. The leaves of the firstyear plant form a bright-green, basal rosette. In the second year, the coarse, erect stalk reaches up to 4 ft (1.2 m) with hairy, alternate, lanceolate leaves with a distinctive mid rib. Leaves grow from 3–6 in (7.6–15.2 cm) long.

The blossoms are pale yellow with a slight lemon scent and a cup-like shape. They grow in clusters along the flower stalk, and bloom from June to September, opening at dusk to attract pollinating insects and night-flying moths. These phosphorescent blossoms inspired a common name for the herb: evening star. The seeds grow within an oblong, hairy capsule. The root is large and fleshy.


General use

The medicinal components of evening primrose are found in the seed-extracted oil, which contains essential fatty acids including gamma linoleic acid (GLA). GLA is often deficient in the Western diet and is needed to encourage the production of prostraglandins. Low levels of essential fatty acids may increase the symptoms of premenstrual syndrome (PMS), diabetes, etc. Evening primrose oil has been used to treat PMS and menopausal symptoms, asthma, and has been shown to reduce high blood cholesterol levels.

Research conducted in Great Britain has indicated that evening primrose oil can also be medicinally useful in the treatment of nerve disorders, such as multiple sclerosis and rheumatoid arthritis.

The essential oil does appear to be of some benefit in cases of alcohol poisoning and in alleviating hangovers, and to ease symptoms of alcohol withdrawal. The oil can also help relieve dry eyes, brittle nails, and acne when combined with zinc. When taken as a supplement, evening primrose has helped to promote weight loss.

Traditionally, Native Americans valued evening primrose as a treatment for bruises and cuts. The Flambeau Ojibwe tribe soaked the whole plant in warm water to make a poultice for healing bruises and to overcome skin problems.

The mucilaginous juice in the stem and leaf can be applied externally to soothe skin irritations, or may be eaten to relieve digestive discomfort and for its stimulating effect on the liver and spleen. The astringent properties of the plant are helpful to soothe inflamed tissue. The plant has sedative properties and has been used to decrease hyperactivity in children.

The entire plant is edible. The root from the firstyear growth is a nutritious pot herb. Boiled roots taste somewhat like parsnips.

Evening primrose oil is valued for its antioxidant properties. Antioxidants are substances that counteract the damaging effects of oxidation in living tissue. A team of Canadian researchers has recently identified the specific antioxidant compounds in evening primrose oil; one of them, a yellow substance known as catechin, appears to inhibit the growth of cancerous tumors and to lower the risk of heart disease.


Preparations

Evening primrose oil is prepared commercially and widely available in health food stores. The extract should be stored in a cool, dry place in order to avoid spoilage. Capsules are also available. Correct dosage should be decided in consultation with a practitioner.

An ointment can be prepared by mixing one part of the diced plant with four parts of heated petroleum jelly. Stored in a tightly closed container and refrigerated, the consistent preparation will maintain its effectiveness. Apply as needed to soothe the skin.

Precautions

Use by persons with epilepsy is discouraged because evening primrose oil appears to lower the effectiveness of medications used to treat epilepsy. Physicians should be consulted before using evening primrose oil on children.

Side effects

There have been some reports of headache, nausea, loose stools, and skin rash after using evening primrose preparations.

Evodia fruit

Evodia fruit is the small, reddish fruit of the plant Evodia rutaecarpa. This plant is native to northern China and Korea, although it is cultivated as an ornamental landscaping plant in many other places in the world.

E. rutaecarpa is a deciduous tree that grows to a height of about 30 ft (10 m) along the sunny edges of woodlands and in suburban settings as an ornamental. It has long, dark green, shiny leaves and blooms with many small clusters of white flowers in the summer.

The fruit, which is the part of the plant used in healing, is reddish when it appears in August and darkens to black by November. The fruit is harvested for medicinal purposes when it is not yet ripe and reddish brown in color. It is then either used fresh or dried. Evodia fruit is also known by its Chinese name wu zhu yu and is called gosyuyu in Japan.


General use

Evodia fruit has been used since at least the first century A.D. in traditional Chinese medicine (TCM). It is characterized as having a warm nature and an acrid, bitter, slightly toxic taste, although the fruit is quite fragrant.

Taken internally, evodia fruit is used to treat symptoms of abdominal distress. These include nausea, vomiting, and diarrhea. It is said to be especially effective in treating morning diarrhea. Evodia is used to stimulate the appetite and to treat abdominal symptoms associated with lack of interest in food.

Evodia is also used as a painkiller. It is a remedy for headaches, especially headaches associated with nausea and vomiting. Traditional Chinese herbalists also use it to treat pain in the upper abdomen and pain associated with abdominal hernias. According to Chinese herbalism, the warm nature of the evodia fruit counteracts cold conditions in the stomach.

There are several other reported uses of evodia fruit. The root bark taken internally is considered useful for expelling parasitic tapeworms and pinworms. The fruit is also believed to have contraceptive properties. Various healers report that the fruit also has anti-inflammatory, anti-tumor, anti-viral, astringent, and diuretic properties. Although evodia fruit has been used for thousands of years in China, its use has recently increased in Japan.

Scientists, primarily from Japan and China, have undertaken laboratory studies of evodia fruit to determine which traditional uses are supported by modern medical findings. Chinese researchers in Taiwan have consistently reported that extracts of evodia fruit interfere with blood clotting. In the future, this finding could be of significance in treating stroke.

Japanese researchers have discovered that in test tube studies extracts of evodia fruit strongly inhibit the growth of one specific bacteria (Helicobacter pylori, a bacteria usually treated in mainstream medicine with antibiotics). Unlike conventional antibiotics, the extract did not alter the growth patterns of any other intestinal bacteria. This finding supports the traditional use of evodia fruit in digestive disorders.


Other Japanese researchers have found that compounds extracted from dried evodia fruit have anti-inflammatory and pain reducing properties in dogs. Reduction of pain is believed to occur because the compounds interfere with pain receptors.

Preparations

Evodia fruit can be used fresh, or it can be dried and ground into a powder for medicinal use. Powdered evodia fruit is sometimes mixed with vinegar to make a paste that is applied externally to the navel to relieve indigestion. A similar paste is applied to the soles of the feet to treat high blood pressure or directly to sores in the mouth. Powdered evodia fruit is also taken internally.

Evodia fruit is often mixed with other herbs, such as ginger, pinellia root, or coptis, in formulas to control vomiting. In addition, evodia fruit is used in the TCM formulas ilex and evodia to treat symptoms of cold and flu, including fever, chills, swollen glands, and sort throat.

Precautions

Evodia fruit is considered by herbalists to be slightly toxic. They recommend that people not take this herb without supervision to prevent overdose and side effects associated with long-term use. Pregnant women should not use evodia fruit. Women who desire to conceive a child should keep in mind that evodia fruit is thought to have anti-fertility properties.

Side effects

Herbalists consider evodia fruit mildly toxic.

Interactions

Evodia fruit is often used in conjunction with other herbs with no reported interactions. Since evodia fruit has been used almost exclusively in Chinese medicine, there are no studies of its interactions with Western pharmaceuticals.