Eucalyptus globulus LABILL. ++

MEDICINAL

P L A N T S

Eucalyptus globulus  LABILL. ++

  

By

Rettodwikart Thenu

EUCALYPTUS GLOBULUS  LABILL. ++

Eucalyptus

HISTORICAL NOTE Indigenous Australians traditionally used eucalyptus to treat fevers and respiratory infections, accounting for its name ‘fevertree’. European settlers also recognised the medicinal qualities of eucalyptus and surgeon Considen is credited with producing the first essential oil sample in 1788. Bosisto investigated oils from several Australian plants and in 1854 eventually produced essential oils commercially in association with Müeller, a pharmacist. Bosisto and Müeller concentrated on oils rich in 1,8-cineole, which includes Eucalyptus species. In the late 1800s, articles about its medicinal use appeared in medical journals such as The Lancet, focusing on its potential in scarlet fever and diphtheria (Braun, L and Cohen, M. 2010).

Eucalyptus !

(yew-kuh-lip’tuhs)

Scientific name: Eucalyptus globulus

Other common names: Blue gum, fever tree, gum, red gum, stringy bark tree, Tasmanian blue gum

BOTANICAL DESCRIPTION (Ross, I. A. 2001)

A small to large tree of the MYRTACEAE family that secretes resinous gums, and often has flaky bark. The leaves are simple, opposite, coriaceous, variously shaped and sized, sometimes aromatic. The flowers are axillary of terminal panicles or subumbels. The calyx consists of a calyptra covering the flower bud, corolla absent, stamens numerous and often white, and the ovary inferior. The fruit is a woody capsule opening by means of slits.

BOTANICAL NAME/FAMILY

Eucalyptus species (family Myrtaceae)

The species most commonly used in healthcare are:

v Eucalyptus globulus (blue gum)

v Eucalyptus citriodora (lemon scented gum)

v Eucalyptus dives (broad leaf peppermint)

v Eucalyptus polybractea.

There are more than 500 species of eucalyptus trees and shrubs native to Australia, but many species are cultivated in other parts of the world.

ORIGIN AND DISTRIBUTION (Ross, I. A. 2001)

The genus Eucalyptus consists of about 600 species, most of which are native to Australia. Many are now introduced throughout the tropical and warm-temperate regions of the world.

   

        Figure 1. Eucalyptus (Eucalyptus globulus).             Figure 2. Eucalyptus – dried drug substance (leaf).

(Barnes, J et al., 2007)

M E D I C I N A L   U S E S

USES (Linda, S-R. 2010)

Eucalyptus is used to treat nasal/pulmonary congestion and appears frequently as a component in combination products used for sinusitis and pharyngitis. It is also used as an antispasmodic to treat irritable bowel syndrome; as a treatment for gallstones, kidney stones, and cystitis; as a central nervous system stimulant; and as an aromatherapeutic agent. Eucalyptus can be used topically as an antiseptic for wounds.

INVESTIGATIONAL USES (Linda, S-R. 2010)

Studies are underway to determine the effi cacy of eucalyptus in the treatment of infections caused by bacteria or fungi, infl ammation, and diabetes mellitus.

FOOD USE (Barnes, J et al., 2007)

Eucalyptus is listed by the Council of Europe as a natural source of food flavouring (leaves, flowers and preparations: category N4, with limits on eucalyptol) (see Appendix 3).(G17) Both eucalyptus and eucalyptol (cineole) are used as flavouring agents in many food products.(G41) Previously in the USA, eucalyptus was approved for food use and eucalyptol was listed as a synthetic flavouring agent.(G41)

HERBAL USE (Barnes, J et al., 2007)

Eucalyptus leaves and oil have been used as an antiseptic, febrifuge and expectorant.(G2,G41, G64)

TRADITIONAL MEDICINAL USES (Ross, I. A. 2001)

Bolivia. Infusion of the dried leaf is taken orally as an expectorant for coughs and respiratory congestion. The extract is also used externally to kill fleas ^E00202.

China. Hot water extract of the dried entire plant is used externally to promote eschar formation in burn treatment ^ECOM.

France. Hot water extract of the leaf is taken orally as a hypoglycemic ^EGOI43

Guatemala. Decoction of the leaf is taken orally for fever ^C016. Hot water extract of the dried leaf is used externally for ringworm, fungal skin diseases ^EGOTSJ, wounds, ulcers, bruises and sores, pimples and pustules, as a douche for vaginitis and leucorrhea, and as a wash for infections of the skin and mucosa Ecom. The extract is taken orally for diabetes, as a febrifuge and sudorific, and for kidney diseases ^EGO217.

India. The leaf essential oil is used externally as a mosquito repellant and an insecticide ^ECOM.

Italy. Infusion of the dried leaf is used in inhalation therapy to treat bronchial asthma, and is taken orally as a cholagogue and to treat diabetes ^ECO162.The hot water extract is taken orally for inflammations ^ECO174.

Kenya. The fresh and the dried leaf are used to control snail infestation ^{Eco196 •}

Mexico. Hot water extract of the dried leaf is taken orally as an antigrippe medication, for urethritis, laryngitis, cystitis, pyelonephritis, gastritis, enteritis, bronchitis, as an antimalarial and antipyretic. The extract is used externally as an antiseptic ^Ecozo4.

Mexico. Infusion of the shade-dried leaf is taken orally to treat infectious diseases ^Eco131.

Peru. Decoction of the twig is taken orally for pulmonary ailments and colds ^EGo163.

Spain. Essential oil of the fruit and leaf are used in inhalation therapy for the treatment of colds and catarrh. The decoction is taken orally for catarrh EGoiso. Hot water extract of the leaf is taken orally for diabetes ^Ecou6.

Tunisia. Hot water extract of the dried leaf is taken orally for bronchial conditions and coughs. Externally, it is used as a mouthwash for dental pain ^Ecozo3.

USA. Hot water extract of the leaf is taken orally as a stimulating expectorant ^LD0715.

West Indies. Hot water extract of the leaf is taken orally for asthma and diabetes ^EG0199.

ACTIVITIES  (Duke, J. A et al., 2002)

Analgesic (1; TRA); Anesthetic (1; CRC); Anthelminthic (1; TRA); Antibacterial (1; BGB; TRA; WAM); Antidiabetic (1; APA); Antiinflammatory (1; PHR); Antiproliferative (1; PHR); Antipyretic (1; BGB; CAN; CRC); Antiseptic (1; APA; TRA; ZUL); Antispasmodic (1; KOM; PIP); Antitumor (1; APA); Antitussive (1; PH2); Antiviral (1; APA; JBU; PHR); Astringent (1; APA; WBB); Bronchodilator (1; WAM); Carminative (f; WBB); Decongestant (1; APA; VAG); Deodorant (1; PHR); Diuretic (1; PHR); Expectorant (2; PIP; TRA; WAM); Fungicide (1; JBU); Hyperemic (2; JFM; KOM); Hypoglycemic (1; HHB; PHR); Insecticide (f; CRC); Insectifuge (f; CRC); Memorigenic (1; APA); Rubefacient (f; CRC); Secretolytic (1; PHR); Secretomotoric (1; KOM; PIP); Sedative (1; TRA); Sialagogue (1; APA); Stimulant (1; CRC; JFM); Vermifuge (1; CRC; TRA; WBB).

CHEMICAL CONSTITUENTS (Ross, I. A. 2001)

(ppm unless otherwise indicated)

Alkanes (C-23 to C-31 ): Lf Wax ^EG0124

Amyrin, beta: Wood 9.3 ^EGD122

Apigenin: Lf ^EG0139

Aromadendrene: Lf EO 0.86-3.6% ^EG0177,^EG0151, FrEO ^EG0147, Twig 2.0% ^EG0146

Aromadendrene, allo: Fr EO 23.3% ^EGDl85, Lf

EO 0.2-0.8% ^EG0177,^EGD151 1 Twig 0.6% ^EGD146

Aromadendrene, alpha: Fr EO ^EGD188

Aromadendrin, 3-methoxy: Resin ^EGDlS?

Aromadendrin, 7-methoxy: Resin ^EG0157

Benzoquinone, para 2,6-dimethoxy: Bk ^EG0122

Betulic acid methyl ester: Wood 14.1 ^EGD122

Betulinic acid, acetyl: Wood ^EGOM

Bicostol: Lf EO ^EG0117

Borneol: Fr EO ^EGD147, Lf EO 0.2% ^EG01SL, Twig w/Lf 0.3% ^EG0146

Borneol acetate: Fr EO ^EG0147

Bulnesene, alpha: Fr EO 5.95% ^EGOLSS

Cadinene, delta: Lf EO ^EG0126

Cadinene, gamma: Lf EO 0.1 % ^EGOl51, Fr EO ^EG0188

Calyptoside: Lf ^EG0143

Camphene: Fr EO ^EG0147, Lf EO 0.51% ^EGDl 77

Caproic acid: Fr EO ^EG0147

Caryophyllene: Lf EO 16.7% ^EGD141

Caryophyllene oxide: Lf EO 0.3% ^EG0151

Catechin(+): Lf ^T14766

Cedrene, beta: Lf EO ^EG0127

Chrysin: Lf ^EG0193

Cineol, 1-8: Lf EO 23.6-64.5% ^EGD141, ^EG0178, Fr EO 20.81-72.5% ^EG018S,^EGD172, Twig w/Lf 72.8% ^EG0146

Citra!: Fr EOEG0147

Citronella!: Lf EOEGolss

Citronellol: Lf EO 13.6%EG0141

Copaene, alpha: Lf EO 0.2% ^EGD151

Cryptone: Lf EO 8.6-16.7% ^EG0141

Cubebene, beta: 0.1 % ^EG0141

Cymene, para: Lf EO 0.5-14.6% ^EGD177,^EG0153

Daugosterol: Wood 6.1 ^EGOLN

Ellagic acid: Lf ^EGONS,^EGD139

Ellagitannin: Lf ^EG0139

Eremophilene: Fr EO ^N°1115

Erythrodiol: Wood 10.1 ^EG0122

Eucalyptin: Lf ^EG0193

Eucalyptin, 8-demethyl: Lf ^EG0193

Eucalyptone: Lf 2 7.4 ^EG0121, ^EG0120

Eucalyptus globulus substance EK: Bud 0.43% ^EG0192

Eudesmol: Fr EO ^EG0147

Eudesmol, alpha: Lf EO 1.7% ^EG0151

Eudesmol, beta: Lf EO 1.3% ^EG0151

Eudesmol, gamma: Lf EO 0.6% ^EG0151

Euglobal 1-A-1: Bud ^EGOLGS,^EGOl91

Eugloball-A-2: Bud ^EG0195,^EG0191

Euglobaii-B: Bud ^EG019S, ^EG0191, Lf ^EG0210

Euglobal 1-C: Lf ^EG021o, Bud ^{EG0195,EG0191}

Euglobal II-A: Bud ^EG0195,^EG0191, Lf ^EG021O

Euglobal 11-B: Bud ^{EG019S,EG0191}

Euglobaiii-C: Bud ^{EG0195,EG0191}

Eugloballll: Lf 10, Bud 100 ^EG0190

Euglobal IV: Bud ^EG0191

Euglobal IV-A: Lf ^EG0194

Euglobal IV-B: Lf ^EG0194

Euglobal V: Bud ^EG0191

Euglobal VII: Bud ^EG0191

Farnesol, cis-trans: Fr EO 9.95% ^EGOl85

Fenchone: Fr EO ^EG0147

Fenchone, iso: Lf EO 0.38% ^EG0177

Gallic acid: Lf ^EG0139

Geraniol: EO ^EG0173

Geraniol acetate: EO ^EGO173

Globulol: Fr EO ^EG0188, Twig w/Lf 1.3% ^EG0146, Lf EO 1.3-3.44% ^EG0151,^EG0177

Globulol, epi: Lf ^EOL02117

Guaiene, alpha: Fr EO 3.15% ^EG01Bs

Gurjunene, alpha: Fr EO ^EGOlBB, Lf EO 0.6% ^EG0151

Hexane, iso-propyl: Lf EO ^EG0141

Hyperoside: Lf ^EG0142

Isoamyl alcohol: Fr EO ^EG0147

Ledol: Lf EO ^L02117, Twig w/Lf 0.2% ^EG0146

Limonene: Lf EO 3.1-5.2% ^EG0177,^EG0178

Limonene (+): Lf EO ^EGOllO

Linalool: Twig w/Lf 0.2% ^EG0146, Lf EO 0.2% ^EG0151

Linalool acetate: Lf EO 1.8% ^EG0141

Linalool oxide: Lf EO 1.9% ^EG0141 , Fr EO ^EG0188

Linoleic acid: Fr Fixed Ojj ^EG0123

Luteolin: Lf ^EG0139

Macrocarpal A: Lf 1 og ^EGOlZl I Calyx 280 ^EG0119

Macrocarpal B: Lf 13 ^EG0121 , Calyx 180 ^EG0119

Macrocarpal C: Lf 22 ^GECOM, Calyx 430 ^EG0119

Macrocarpal D: Lf 18.2 ^EG0121 , Calyx 250 ^EG0119

Macrocarpal E: Calyx 150 ^EG0119

Macrocarpal H: Lf 23.o ^EGO121

Macrocarpal 1: Lf 23.o ^ECO121

Macrocarpal J: Lf 28.4 ^EG0121

Maslinic acid: Lf ^EG0170

Menthane, para: Fr EO ^EG0147

Myrcene: Fr EO ^EG0147, Lf EO 0.1% ^EG0151,

Twig w/Lf 0.5% ^EG0146

Myristic acid: Fr fixed oi1 ^EG01 47

Myrtenol: Fr EO ^EGO147

Ocimene, beta trans: Lf EO 0.1 % ^EGo1s1

Oleanolic acid: Lf ^EGOl?O

Oleanolic acid, acetyl: WoodEGom

Oleanolic acid, para-methoxy-ciscinnamoyl:

Wood 2.7EGo122

Oleic acid: Fr fixed oi!EG0123

Palmitic acid: Fr fixed oil ^EG0123

Phellandrene, alpha: Lf EO 0.1-34.3% ^EG0151,^EG0153, Fr EO B.3% ^EG01BS, Twig w/Lf 0.3% ^EG0146

Phellandrene, alpha (-): Lf EO ^TOZS&O

Phellandrene, beta: Fr EO 3.43% ^EG01BS, Lf EO 3.6% ^EG0141

Phenol, 2,4,6-trimethoxy: Bk ^EG0122

Phenol, 3,4,5-trimethoxy: Bk ^ECOM

Pinene: Lf ^L0071S

Pinene, alpha: Lf EO 0.5- 26.0% ^I15237,^EG01Bs, Fr EO 4.09% ^EG0185, Twig w/Lf 11.9% ^EG0146

Pinene, beta: Lf EO 0.5% ^EG0151, Fr EO ^EG0188, Twig w/Lf O.l% ^EG0146

Pinocarveol, trans: Lf EO 0.94% ^EG0177, Twig w/Lf 1.6% ^EG0146, Fr EO ^EG0147

Piperitone; Fr EO ^EGOlBB, Twig w/Lf 0.1 ^EG0146

Proanthocyanidin: Lf ^EGOBB

Procyanidin B-2,3-0-galloyl: Lf ^EG0171

Prodelphinidin B-2,3-0-galloyl: Lf ^EG0171

Prodelphinidin B-2,3,3-di-0-galloyl: Lf ^EG0171

Prodelphinidin B-5: Lf ^EG0171

Prodelphinidin B-5,3,3-di-0-galloyl: Lf ^EG0171

Pulegole, iso: Lf EO 0.2% ^EG0141

Quercetin: Lf ^EG0142

Quercitrin: Lf ^EG0139

Quercitrin, iso: Lf ^EG0142

Rutin: Lf ^EGD142

Sabinene: Fr EO ^EG0147

Sakuranetin: Resin ^EG0157

Scyll ito I: Lf ^EG0224

Selinene, alpha: Lf EO 0.2% ^EGD151

Sideroxyl in: Lf ^EG0193

Sideroxylin, 8-demethyl: Lf ^EGD193

Styrene alpha para-demethyl: twig w/Lf 0.3% ^EG0146

Terpin-1-en-4-ol: EO 0.1 % ^EG0173

Terpinen-4-ol: Fr EO ^EGOLSS, Lf E00.8% ^EG0151, Twig w/Lf 0.3% ^EG0146

Terpinene, alpha: Fr EO ^EGOlBB

Terpinene, beta: Fe EO ^EGOLSS

Terpinene, gamma: Lf EO 0.1-8.9% ^{EGD151,EGD153}, Fr EO ^EG0188

Terpineol, alpha: Lf EO 2.9- S.8% ^{EG0141,EG0151}, Fr EO ^EG0147

Terpineol, alpha acetate: Lf EO 2.09% ^EG01771 twig w/Lf l.l% ^EG0146

Terpinolene: Lf EO 0.1-0.5% ^EGD151,^EG0141

Thujone, alpha: Fr EO ^EG0147

Thujone, beta: Fr EO ^EGO147

Thymol: Fr EO ^EGO147

Tocopherol, alpha: Lf 333 ^Kl6666

Tritriacontan-16, 18-dione: Lf Wax ^M14832

Tritriacontan-18-one, 16-hydroxy: 7 .s ^EG0116

Tritriacontane-16, 18-dione, 4-hydroxy: Lf 6 ^EG0116

Ursolic acid: Wood 8.1 ^EG0122

Ursolic acid, acetyl: Wood 48.8 ^EG0122

Ursolic acid, para-methoxy-cis-cinnamoyl: Wood 3.3Ecom

Ursol ic acid, para-methoxy-transcinnamoyl: Wood 4.2 ^EGOLN

Uvaol: Wood 12.8 ^EG0122

Valeraldehyde: Lf ^L00715

Verbenol, trans: Fr EO ^EG0147

Verbenone: Fr EO ^EGD147, Twig w/Lf 0.1 % ^EG0146

Viridiflorol: Lf EO ^L02117

Vomifoliol: Bk ^EG0122

PHARMACOLOGICAL ACTIVITIES AND CLINICAL TRIALS (Ross, I. A. 2001)

Abortifacient effect. The leaf essential oil, administered subcutaneously to pregnant mice at a dose of 135.0 mg/kg on days 6-15 of gestation, was inactive ^E00219.

ACTH-induction. The dried leaf, in the ration of opossum at variable concentrations, was inactive ^E00107.

Analgesic activity. The essential oil was applied on the forehead and temple areas of 32 healthy adults in a double-blind, placebo-controlled, randomized cross-over study. Four different test preparations were applied to large areas of the forehead and temples using a small sponge. The effects were then evaluated by comparing baseline and treatment results. The combination of peppermint oil, eucalyptus oil, and ethanol increased cognitive performance and had a muscle-relaxing and mentally relaxing effect, but had little influence on pain sensitivity. A significant analgesic effect with a reduction in sensitivity to headache was produced by a combination of peppermint oil and ethanol ^E00161. The leaf essential oil was applied externally with alcohol to 32 volunteers in a randomized, double-blind, placebo-controlled study. The effect was described as muscularly and mentally relaxing, but not analgesic ^E00158.

Anthelmintic activity. Ether extract of the leaf was active on Strongyloides atercorafisEoom.

Antiamoebic activity. The essential oil, in broth culture at a concentration of 4.0 microliters/ml, was active on Entamoeba histolytica ^E00155.

Antiancylostomiasis activity. Ether extract of the leaf was active on Ancylostoma caninum and Ancylostoma duodenaleEoom.

Antibacterial activity. Ethanol (50%) extract of the dried aerial part, in broth culture at a concentration of 25.0 mcg/ml, was active on Staphylococcus aureus ^E00209 . Methanol extract of the shade-dried leaf, on agar plate at a concentration of 0.6 mg/ml, was inactive on Staphylococcus aureus. A concentration of 10.0 mg/ml was inactive on Escherichia coli and Pseudomonas aeruginosa ^E00131. The chromatographic fraction of the dried leaf, on agar plate at variable concentrations, was active on several gram positive organisms ^A11407. The fresh essential oil, on agar plate, was active on Pseudomonas aeruginosa and Staphylococcus aureus, and inactive on Bacillus cereus and Escherichia coli ^Eoozot. Water extract of the leaf, on agar plate, was active on Escherichia coli, MIC 0.07; Staphylococcus aureus, MIC 0.09; Staphylococcus aureus strain Oxford, MIC 0.4; Bacillus subtilis, MIC 0.8 and Enterococcus faecalis, MIC 1.3 mg/ml ^E00166. The leaf essential oil, on agar plate, was inactive on Propionibacterium acnes ^E00125. The leaf essential oil, on agar plate at a concentration of 6.0 microliters/disc, was active on Enterobacter species, Escherichia coli, Haemophilus influenza, Klebsiella species, Proteus mirabilis, Proteus morganii, Proteus rettgeri, Pseudomonas species, Salmonella typhi, Salmonella wien, Staphylococcus aureus, Streptococcus species and Pseudomonas aeruginosa ^E00176. The leaf essential oil on agar plate, was active on Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus ^EG0212. The leaf essential oil, on agar plate, was active on Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus, and inactive on Bacillus cereus ^E00215. Tincture of the dried leaf (10 gm of plant material in 100 ml ethanol), on agar plate at a concentration of 30.0 microliters/disc, produced weak activity on Escherichia coli ^E00218.

Antibacteriophage activity. Ethanol (70%) extract of the fresh leaf, in broth culture, was active on Bacteriophage T2, T4, Type I, MS2, PHI~X0174 and T~7 ^E00159.

Antifungal activity. Aqueous low~speed supernatant of the fresh leaf, in broth cuiture at a concentration of 100.0 ml/liter, produced strong activity on Hendersonula toruloidea ^EG0206. Hot water extract of the dried leaf, in broth culture, was inactive on Epidermophyton fioccosum, Microsporum canis, and Trichophyton mentagrophytes var. granulare and algodonosa ^E00183. The fresh essential oil, on agar plate, was inactive on Penicillium cyclopium, Trichoderma viride, and Aspergillus aegyptiacus E00201. The leaf essential oil, on agar plate, produced strong activity on Aspergillus aegyptiacus, Penicillium cyclopium and Trichoderma viride ^E00215. The leaf essential oil, on agar plate, was active on Aspergillus fiavus, and produced weak activity on Keratinomyces ajelloi, Microsporum gypseum, Trichophyton equinum, Trichophyton mentagrophytes, Trichophyton rubrum, and Trichophyton terrestris ^E00214. The leaf essential oil, on agar plate, was active on Manila sitophila, Trichophyton tonsurans, and Penicillium digitatum ^E00141. The leaf essential oil, on agar plate, was inactive on Trichophyton mentagrophytes ^Eoom.

Anti hyperglycemic activity. Hot water extract of the dried leaf, in the ration of mice at a dose of 6.25% of the diet with the addition of decoction 1 gm/400 ml of drinking water, was active vs Streptozotocin- induced hyperglycemia ^E00180. Infusion of the dried leaf, taken orally by adults at variable dosage levels, was inactive ^E00108. Water extract of the dried leaf, administered intragastrically to mice, was active ^E00136. Water extract of the dried leaf, administered by gastric intubation and intraperito neally to mice, produced weak activity vs alloxan induced hyperglycemia ^E00204. The ethanol (95%) extract, administered by gastric intubation to rabbits at a dose of 1.0 gm/kg, was inactive ^E00115.

Anti-inflammatory activity. Decoction of the dried seed was active vs croton oil induced edema in mice and vs cotton pellet granuloma and carrageenin induced pedal edema in the rat ^E00129. Ethanol ( 80%) extract of the dried leaf, administered by gastric intubation to male rats at a dose of 100.0 mg/kg, produced 18% inhibition of edema vs carrageenin-induced pedal edema ^E00174.

Antimalarial activity. Chloroform extract of the twig, administered orally to chicken at a dose of 264.0 mg/kg, and the water extract at a dose of 3.48 gm/kg, were inactive on Plasmodium gallinaceum ^E00101. Ethanol (95%) extract of the dried aerial part, at a concentration of 100.0 mcg/ml, produced weak activity on Plasmodium falciparum FMN-17, MP-II and SO. A concentration of 150.0 mcg/ml produced weak activity on P. falciparum FAN-5. A concentration of 75.0 mcg/ml was active on P. falciparum FMN -13 ^E00220 . Hexane extract of the dried leaf, administered intragastrically to mice at a dose of 100.0 mg/kg daily for 4 days, was inactive on Plasmodium berghei ^E00144 .

Antimutagenic activity. Methanol extracts of the dried fruit and leaf, on agar plate at a concentration of 50.0 microliters/disc, were inactive on Bacillus subtilis NIG-1125 His Met and Escherichia coU B/R-WP2-TRP ^ROOZOS. Infusion of the leaf, on agar plate at a concentration of 100.0 microliters/disc, was inactive on Salmonella typhimurium TA100 vs ethyl methanesulfonate-induced mutagenicity and on Salmonella typhimurium TA98 vs 2-amino-anthracene-induced mutagenicity.  Metabolic activation was not required for the activity ^E00165. Methanol extract of the dried leaf, on agar plate at a concentration of 50.0 microliters/disc, was inactive on Bacillus subtilis NIG-1125 His Met and Escherichia coli B/R-WP2-TRP ^EOOZOS.

Antimycobacterial activity. Ethanol (95%) extract ^ROO114 and fluid extract ^EG0103 of the dried leaf, on agar plate, were active on Mycobacterium tuberculosis. The activity was lost in the presence of whole blood. The water extract was inactive ^E00114. The leaf essential oil, administered intramuscularly to guinea pigs at a dose of 500.0 mg/kg, was active on Mycobacterium tuberculosis. The treatment enhances the activities of sulfetrone 100 mg/kg, streptomycin 2 mg/kg, and isoniazid 10.0 mg/kg, administered orally ^E00113 .

Antioxidant activity. Hexane and methanol extracts of the dried leaf were equivocal ^EG0145.

Antitumor activity. Ethanol (50%) extract of the dried aerial part, administered intraperitoneally to mice at a dose of 140.0 mg/kg, was inactive on LEUK- P388 ^E00209.

Antiviral activity. Water extract of the dried leaf, in cell culture at a concentration of 10.0%, was active on Influenza virus, Vaccinia virus and Poliovirus II, and produced strong activity on Herpes virus type 2 ^EG0207.

Antiyeast activity. Methanol (50%) extract of the dried leaf, on agar plate, was active on Candida albicans ^EG0221. The tincture {10 gm of plant material in 100 ml ethanol), on agar plate at a concentration of 30.0 microliters/disc, produced weak activit ^F00218. Methanol extract of the shade-dried leaf, on agar plate at a concentration of 1.25 mg/mL, was inactive on Candida albicans ^EOOM. The leaf essential oil, on agar plate, was inactive on Pityrosperum ovale ^E00125. The leaf essential oil, on agar plate, was active on Candida albicans ^EOOM and Cryptococcus neoformans ^EOOJS4.

Cardiovascular effect. Ethanol (50%) extract of the dried aerial part, administered intravenously to dogs at a dose of 25.0 mg/kg, was active ^E00209 .

CNS effect. The essential oil was applied on the forehead and temple areas of 32 healthy adults in a double-blind, placebocontrolled, randomized cross-over study. Four different test preparations were applied to large areas of the forehead and temples using a small sponge. The effects were then evaluated by comparing baseline and treatment results. The combination of peppermint oil, eucalyptus oil and ethanol increased cognitive performance and had a musclerelaxing and mentally relaxing effect, but had little influence on pain sensitivity. A significant analgesic effect with a reduction in sensitivity to headache was produced by a combination of peppermint oil and ethanol ^EG0161 .

Cutaneous absorption effect. The leaf essential oil, applied to the abdomen of mice at a concentration of 0.25%, was active when measured 2 hours after application ^ROO111 .

Cytotoxic activity. Ethanol (50%) extract of the dried aerial part, in cell culture at a concentration of 25.0 mcg/ml, was inactive on CA-9KB ^E00209. Water extract of the dried leaf, in cell culture at a concentration of 10.0%, produced weak activity on Hela cells ^WOZO1.

Diuretic activity. Decoction of the dried leaf, administered nasogastrically to rats at a dose of 1.0 gm/kg, was active ^E00217.

Estrogenic effect. The leaf essential oil, administered subcutaneously to ovariectomized mice, was inactive. The treatment was effective on immature female rats. The activity was equivalent to 10 units/ml ^ECOWO.

Expectorant activity. The leaf essential oil, administered orally to cats and rabbits at a dose of 100.0 mg/kg, produced weak activity, was active in rats and inactive in dogs. A dose of 50.0 mg/kg was active in guinea pigs ^E00104.

Hypertensive activity. The chromatographic fraction of the dried leaf, administered intravenously to rabbits at variable dosage levels, was inactive ^A011407.

Hypotensive activity. The chromatographic fraction of the dried leaf, administered intravenously to rabbits at variable dosage levels, was inactive ^A011407.

Insect repellent activity. The leaf essential oil (12 part), in a mixture of pennyroyal oil (24 part), cedar oil (6 part), citronella oil ( 6 part) and rue oil ( 1.5 part) formulated (2-7%) in an organic solvent, paraffin wax, petrolatum, soap, and cotton rope was effective for fleas on dogs ^E00200. The leaf essential oil was active on Pediculus human us humanusw ⁰¹⁶⁴.

Insecticide activity. The leaf essential oil, at a concentration of 0.8%, was active on mites (Pyroglyphidae) ^E00148. The leaf essential oil, at a concentration of 0.002%, in a mixture containing 0.01% Ocimum sanctum essential oil and 0.002% Ocimum basilicum essential oil, produced 100% mortality on Culex fatigans larvae ^E00208.

Larvicidal activity. The essential oil, at a concentration of 25.0 ppm, was active on the Anopheles stephensi larvae ^E00216.

Molluscicidal activity. Water extracts of the dried and fresh leaf, at a concentration of 1:500, were active on Ancylostoma ceylanicum, Biophalaria species, Bulinus species, and Physopsis species ^E00196.

Mutagenic activity. Tincture of the leaf, on agar plate at a concentration of 80.0 microliters/disc, was inactive on Salmonella typhimurium TAlOO and TA98. Metabolic activation had no effect on the results ^E00152.

Radical scavenging effect. Ethanol (50%) extract of the dried entire plant, at a concentration of 5.0 mcg/ml, produced weak activity vs superoxide anion, estimated by the neotetrazolium method ^E00156.

Repellent activity. Methanol extract of the dried leaf, at a concentration of 4.0 mg/squareem, was equivocal on Mytilus edulis ^E00118.

Rubefacient effect. The leaf essential oil was applied externally with alcohol to 32 volunteers in a randomized, double-blind, placebo-controlled study. The effect was described as muscularly and mentally relaxing but not analgesic ^E00158.

Teratogenic activity. The leaf essential oil, administered subcutaneously to pregnant mice at a dose of 135.0 mg/kg on days 6 to 15 of gestation, was inactive ^E00219.

Toxic effect. Fatalities have been reported after the ingestion of doses between 4 and 480 ml of the essential oil. Toxic symptoms include gastrointestinal pain, vomiting, diarrhea, CNS depression, coma, miosis, seizure (usually in children), feeling of suffocation and muscular weakness. Treatment is supportive and may include gastric lavage and charcoal ^EGoisi. The chromatographic fraction of the dried leaf, administered subcutaneously to rabbits at a dose of 0.2 mg/kg daily for 2 weeks, was inactive ^A011407. The leaf essential oil, in the bath water, produced burning, redness and irritation on the skin of a child. When taken orally by an adult, vomiting, mild CNS depression, apnea and cardiac arrythmias were observed ^E00182. The leaf essential oil, taken orally by a child at a dose of 10 to 15 ml, produced symptoms that included pallidity, lethargy coolness of the skin and dyspnea ^E00149.

Toxicity assessment. Ethanol (50%) extract of the dried aerial part, when administered intraperitoneally to mice, produced an LD₅₀ 562.0 mg/kg ^E00209 . The leaf essential oil,  when administered intragastrically to mice, produced an LD₅₀ 3.32 gm/kg ^E00175 . The leaf essential oil, when administered orally to rats, produced LD₅₀ 4.44 gm/kg ^EOOT9S.

Tyrosine inhibition. The dried aerial part, in cell culture at a concentration of 500.0 mcg/ml, was inactive on melanoma-B16 ^E00134.

MAIN ACTIONS (Braun, L and Cohen, M. 2010)

The main reported actions are expectorant, antitussive (Misawa & Kizawa 1990), nasal decongestant (Burrows 1983, FDA 1994), analgesic (Gobel 1995) and antispasmodic in animal and human studies. Antimicrobial and anti-inflammatory activity has also been reported in animal and human studies.

Antitussive Antitussive effects were compared with codeinein guinea pigs in which cough was mechanically stimulated. Essential oil 5% in normal saline was administered by inhalation and had a significant antitussive effect relative to codeine (P < 0.05) (Misawa & Kizawa 1990). The antitussitive effects of 1,8-cineole were demonstrated in humans in 1980 in a single blind cross over study in healthy volunteers using a commercially available chest rub where eucalyptus was the active ingredient in the blend (Packman & London 1980). It appears that 1,8-cineole interacts with the M8 (TRPM8) receptor potential channel, the cool-sensitive thermoreceptor primarily affected by menthol, which produces a cooling sensation (Behrendt et al 2004). However, the antitussive effect may also be due to an effect on pulmonary C-fibres, which also contain TRPM 8 receptors.

Nasal decongestant Two clinical studies have demonstrated that inhalation of eucalyptus oil reduces nasal congestion (Burrows 1983, FDA 1994). Likewise, Cohen & Dressler (1982) showed statistically significant differences in patients with acute coryza inhaling a volatile mixture of menthol 56% and eucalyptus oil 9% for 20 minutes compared to a control group on 14 of the 22 indices of respiratory function, measured from baseline to 60 minutes after inhalation. In contrast, Burrows et al (1983) showed no decongestant effect of inhaling camphor, eucalyptus or menthol for five-minute periods via a face mask (n = 31), although cold receptors in the nose were stimulated, creating a sensation of increased airflow and improved comfort.

Antimicrobial Previous studies indicate eucalyptus has antimicrobial activity in vitro against Pseudomonas aeruginosa, Bacillus subtilis, Enterococcus faecalis and Escherichia coli (Kurrerath & Mundulaldo 1954), herpes simplex (Schnitzler et al 2001) and oral pathogens (Takarada et al 2004). A clinical observational study involving 30 patients with head and neck cancer and necrotic malodorous ulcers demonstrated improved quality of life and social interaction with the addition of a twice daily cleansing of the ulcers with an essential oil mix whose main component was eucalyptus (Warnke et al 2006). In addition, the researchers reported evidence of re-epithelialisation and antiinflammatory effects.

Anti-inflammatory Eucalyptus inhibits prostaglandin synthesis in vitro (Wagner 1986) at a concentration of 37 micromol/L. Anti-inflammatory and antinociceptive effects have been demonstrated in animal models (Ulbricht & Basch 2005). Alternatively, a study in which 1,8-cineole was injected into the rat hindpaw demonstrated that eucalyptus induced oedema, most likely due to the release of mast cell mediators (Santos & Rao 1997). The clinical implications of this finding for topically applied eucalyptus oil require further investigation. Anti-inflammatory activity of E. radiata has been demonstrated in patients with dry and weeping dermatitis, most probably due to inhibition of inflammatory markers such as TNF-alpha, COX enzymes, 5-lipoxygenase and other leukotrienes, and it could be an alternative to topical steroid medicines (Hadji-Minglou & Bolcato 2005, Santos & Raos 2000). Juergens et al (2003) demonstrated 1,8-cineole maintained lung function four times better than controls in a double blind clinical trial of patients (n = 32) with severe steroid-dependent bronchial asthma. Patients were randomly assigned to 1,8-cineole 200 mg 3 times daily for 3 weeks or placebo. Steroid doses were reduced by 2.5 mg every 3 weeks. Twelve of the 16 receiving 1,8-cineole remained stable despite reduced steroid doses.

Analgesic Analgesic properties are attributed to the monoterpene components of eucalyptus oil. The monoterpenoid profile differs among eucalypt species and may account for variations in therapeutic effect. E. globulus has a high 1,8-cineole content (60–90%) (Juergens et al 1998). Silva et al (2003) investigated the analgesic and anti-inflammatory effects of E. tereticornis, E. citriodora and E. globulus in rats. The results showed central and peripheral analgesic effects of the three oils.

OTHER ACTIONS (Braun, L and Cohen, M,. 2010)

Eucalyptus oil is metabolised in the liver; however, evidence is contradictory as to whether it induces the cytochrome P450 enzyme system. One study conducted with an animal model demonstrated a slight increase in CYP4A expression (Ngo et al 2003), whereas 1,8-cineole has demonstrated CYP450 induction in vitro and in animal studies (Ulbricht & Basch 2005). E. globulus induces a cellmediated immune response, and morphological and functional activation in human macrophages stimulates the phagocytic response (Serafino et al 2008).

CLINICAL USE (Braun, L and Cohen, M,. 2010)

Eucalyptus oil has been investigated in numerous forms; however, there is a lack of controlled, clinical studies.

Respiratory conditions Eucalyptus oil is used as symptomatic treatment in obstructive respiratory conditions such as bronchitis, asthma, the common cold and other conditions associated with catarrh of the upper respiratory tract. Although it is used internally and externally in Europe for these indications, in Australia the oil is generally used externally in vaporisers, chest rubs and nasal inhalations. Nasal decongestant properties were assessed in 31 healthy volunteers using inhalations of 10 mL of essential oil for 5 minutes. There was no effect on nasal resistance to air flow, but there was a stimulant effect on the cold receptors in the nose and the majority of subjects reported being able to breathe more easily (FDA 1994). A single-blind, parallel clinical trial (n = 234) was conducted to assess whether vaporised essential oil reduced nasal congestion compared with steam. The essential oil was significantly more effective (P < 0.02), but only in the first hour after inhalation. Other researchers found no significant differences in nasal decongestion compared with placebo (Burrows 1983). There was no significant difference between placebo and topically applied E. piperita to the forehead and temples to treat headache in a randomised, double crossover trial (n = 32); however, cognitive performance and muscle and mental relaxation were greater in the essential oil group (Gobel 1995).

Aromatherapy Eucalyptus, as it is traditionally used in aromatherapy, has not been systematically investigated under clinical trial conditions. Therefore, most evidence is derived from traditional sources. Aromatherapists use eucalyptus for its mentally uplifting and stimulating effects and to aid concentration. It is also used in massage and vaporisers to relieve respiratory symptoms, treat minor skin infections and acne, and relieve headache and muscular aches and pain. Usually eucalyptus oil is included in a blend of 3–5 essential oils for a massage but may be used alone for an inhalation. One study investigating the effects of topical application of eucalyptus oil to the forehead and temples found it was an ineffective treatment for headache (Gobel 1995).

OTHER USES (Braun, L and Cohen, M,. 2010)

Eucalyptus oil is often included in OTC and other medicines in various formulations such as rubs, mouthwashes, ‘cold and ’flu’ preparations, cleansing products, inhalers, soaps and insect repellents in which the 1,8-cineole content is standardised to 80–90%. Bosisto’s Eucalyptus Oil is commonly sold in supermarkets and has an Aust R label (10908). It is not used in aromatherapy and is dispensed in a ribbed poison bottle with a childproof cap.

Dust mite removal Eucalyptus oil can be formulated with a kitchen detergent concentrate to form an inexpensive acaricidal wash that reduces the number of live mites found in blankets during normal machine washing (Tovey & McDonald 1997). When compared with detergent concentrate alone, a 30-minute pre-wash soak of woollen blankets with the eucalyptus oil/ detergent formula reduced the number of live mites that could be recovered by 97%. This eliminates the need for very hot water and may maintain low allergen levels in bedding for longer than normal laundering alone because mites are adversely affected by low concentrations of eucalyptus oil vapour, which lingers for 2–3 days. In this study, the dishwashing liquid detergent concentrate (Kit, L&K, Rexona, Sydney, Australia) was used to form an emulsion in water because the essential oil is not soluble in water.

Cleaning agent Washing in diluted eucalyptus oil is also used as a method of removing stains from fabric; however, it does leave a faint characteristic odour for 2–3 days despite rinsing and drying, and some people may find this irritating.

Malodorous necrotic ulcers These ulcers are a major concern for cancer patients and can lead to social isolation and reduced QOL because current treatments inadequately reduce the foul smell to acceptable levels. A paper published in 2006 reported that rinsing the ulcers twice a day with an antibacterial essential oil mixture (mainly eucalyptus oil) resulted in complete disappearance of odour by day 3 or 4 in all patients (n = 30) (Warnke et al 2006). The eucalyptus was used in combination with a standard course of antibiotics. A number of beneficial secondary findings were anti-inflammatory activity, promotion of healing and complete re-epithelialisation, and emotional relief on resolution of the condition.

PRODUCT AVAILABILITY (Linda, S-R. 2010)

Aqueous-alcoholic preparation, essential oil, fl uid extract, lotion, semisolid preparation; eucalyptus is a component of various cosmetics and over-the-counter products used to treat sinusitis and pharyngitis.

Plant Parts Used:  Branch tips, leaves

DOSAGE AND SENSIBLE USE (Chevallier, A. 2018)

As with all medicines, getting the dosage right is essential. Too much and you risk overdosing, too little and the remedy may not work. Follow the guidelines on these pages to ensure that you use herbal remedies safely and appropriately.

ADULT DOSAGES

Each of the remedies listed in the A–Z of Herbal Remedies has a letter indicating its adult dosage—how much of the herb to take per day or per week.

To take an example, passion flower (Passiflora incarnata) on p.173 has C for its dosage. Looking at the dosage guide (right), it can be seen that C = 2–4g a day or 30g a week. Passion flower should therefore be taken at these recommended dosages.

As another example, hawthorn leaf (Crataegus spp.) has M and C for its dosage. M applies to manufactured products: take prepackaged hawthorn products, such as standardized tablets and capsules, at the manufacturer’s recommended dosage. C applies to dried hawthorn leaf or berry: take at the recommended daily or weekly dosage, i.e. 2–4g a day or 30g a week. Similarly, each of the other letters gives specific recommendations on how to use the herb.

Teas and decoctions The dosages given in the guide apply when making teas and decoctions from dried herb material—bark, leaves, roots, etc. For fresh herb material you can use 11⁄2–2 times the quantity of dried material.

Tinctures It is not possible to give clear guidelines for tinctures owing to the wide variation in their strength. Ask advice on dosage when purchasing a tincture. In general, the dosage range for a 1:3 tincture is the same (in milliliters not grams) as the above dosages, i.e. for A, the dosage of a 1:3 tincture is 5–15ml a day.

ADULT DOSAGE GUIDE

Recommended ADULT dosage as given in the key information boxes (see opposite page). For children and people over 70, see below and opposite.

Ø  A = 5–15g a day, or max. 100g (31⁄2 oz) per week

Ø  B = 3–7.5g a day, or max. 50g (2 oz) per week

Ø  C = 2–4g a day, or max. 30g (1 oz) per week

Ø  D = 1–2g a day, or max. 15g (1⁄2 oz) per week

Ø  M = Take product at manufacturer’s recommended dosage.

Ø  T = Topical application on the skin only (Note: preparations made specifically for topical use should not be taken internally.)

Powders Take the minimum recommended daily dosage only.

Tablets and capsules Take at the manufacturer’s recommended dosage.

CHILDREN’S DOSAGES

Do not give babies under 6 months any medication without professional advice.

You may need to adjust dosage levels for children who are particularly small or large for their age.

§  From 6 months to 1 year: give 1⁄10 the minimum adult dose

§  From 1 to 6 years: give 1⁄3 the minimum adult dose

§  From 7 to 11 years: give 1⁄2 the minimum adult dose

§  From 12 to 16 years: give the low adult dose.

DOSAGES FOR OVER 70s

As we age, our bodies become less efficient at breaking down drugs, including herbs. From the age of about 70 onward it is advisable to take slightly lower doses: 80 percent of the standard adult dose is normally recommended. In very old and frail people the dosage may need to be as low as 50 percent of the standard adult dosage.

GENERAL CAUTIONS

v  Do not take essential oils internally unless on advice of a suitably qualified health care professional.

v  Do not give herbs to babies under 6 months old.

v  Do not exceed the recommended dosage levels.

v  If you are taking drugs prescribed by your doctor or hospital, check with them, or with a registered herbal or naturopathic practitioner, before taking a herbal remedy.

v  People known to have allergies should start by taking a low dose and, if this is fine, then increase the dose.

v  Contact allergy can occur on handling fresh or dried herbs. Where such allergy occurs, do not take the remedy internally. Some people are allergic to specific plant families, for example the daisy (Asteraceae) family. Several herbs listed in this book, including chamomile (Chamomilla recutita), echinacea (Echinacea spp.), and feverfew (Tanacetum parthenium), belong to this family and are known to cause contact allergy in sensitive individuals.

KEY INFORMATION (Chevallier, A. 2018)

Every remedy in the A–Z features a key information box that provides essential data on the herb. At the top, each herb is rated using a 5-star rating system, with 5 black stars = most. This gives some idea of the herb’s:

v  overall safety record (Safety)

v  long-standing use in traditional medicine (Traditional use)

v  evidence of effectiveness, as supported by scientific research (Research).

On the line below (Best taken as), suitable types of preparation are recommended; for example, yarrow (Achillea millefolium) is best taken as a tea, which gets 3 checks. Dosage information is provided on the following line. Some entries include an “Often used with” recommendation. The last and most important section lists known cautions for the remedy, and should be read carefully, especially before taking a remedy.

DOSAGES (Linda, S-R. 2010)

NOTE: Dilute internal dosages before use.

v  Adult PO eucalyptol: 0.05-0.2 ml

v  Adult PO eucalyptus oil: 0.05-2 ml or 0.3-0.6 g daily

v  Adult PO fl uid extract: 3 g

v  Adult topical aqueous-alcoholic preparation: 5%-10% prn (Blumenthal,1998)

v  Adult topical essential oil: several drops rubbed into skin prn (Blumenthal,1998)

v  Adult topical oil or semisolid preparations: 5%-20% prn (Blumenthal, 1998)

DOSAGES (Duke, J. A et al., 2002)

1–2 tsp chopped leaf/cup water (APA); 4–6 g leaf/day (KOM; PIP); 4–16 g leaf/day (PHR); 300–600 mg EO (PHR); 1–2 drops EO/cup water; 0.05–0.2 ml EO (CAN; PNC); 0.05–0.2 ml eucalyptol (cineole) (CAN); 2–4 g fluid extract (CAN); single dose 2 g (HHB); 3–9 g tincture (KOM); 3–4 g tincture/day (PHR); steep 8–10 g dry leaf/liter water or 30–40 g fresh leaf, inhale the steam (TRA).

DOSAGE (Barnes, J et al., 2007)

Dosages for oral (unless otherwise stated) administration (adults) for traditional uses recommended in older standard reference texts are given below.

v  Eucalyptol  (cineole BPC 1973) 0.05–0.2 mL.

v  Eucalyptus Oil  (BPC 1973) 0.05–0.2 mL.

v  Fluid  extract 2–4 g.

v  Oil for local application  30 mL oil to 500 mL lukewarm water.

DOSAGE AND DURATION OF USE (Kraft, K and Hobbs, C. 2004)

– Tea: Pour 150 mL boiling water onto 1.5–2 g of the finely chopped drug; cover and steep for 5 to 10 minutes.

– Daily dose: 4–6 g dried leaves. One dose equals 1.5 g dried leaves.

DOSAGE RANGE (Braun, L and Cohen, M. 2010)

Dose recommendations vary, but generally low doses are used. Internal formulations may take longer to show an effect than conventional medicines.

v  Inhalation: 12 drops in 150 mL of boiling water or 5 drops in a nebuliser, which delivers approximately 35 mg (unpubl. data: Harris & Harris –Aromatic Medicine: The Interfaces of Absorption, seminar course notes, Melbourne, 2003). High doses are not recommended because they can irritate the eyes and mucous membranes and may trigger an asthma-like attack.

v  Mouth wash: 20 mL (0.91 mg/mL) solution gargled twice daily.

v  Massage: traditionally aromatherapists use essential oils as 3.5–5% in a carrier substance but doses between 5 and 20% are used for adults and much lower doses for children and older people.

v  Ointments, creams, gels and poultices: 5–10% in a carrier substance such as beeswax.

v  Internal use: 0.3–0.6 mL/day essential oil 1–4 times daily; capsules 100–200 mg; lozenges 0.2–15.0 mg dissolved slowly in the mouth every 30–60 minutes.

Most Australian aromatherapists do not currently administer essential oils via the internal route (oral, vaginal and rectal), but they are administered via these routes in other countries, especially France.

INDICATIONS (Duke, J. A et al., 2002)

Acne (f; PHR); Anorexia (f; PHR); Arthrosis (1; APA; CRC); Asthma (2; IED; PHR; TRA); Bacteria (1; BGB; TRA; WAM); Boil (f; CRC); Bronchosis (2; JFM; PHR; TRA); Burn (f; CRC); Cancer (1; APA; CRC); Catarrh (2; KOM; PIP; TRA); Cholecystosis (f; PHR); Cold (f; CRC; TRA; VAG; WBB); Congestion (1; APA; BGB; VAG); Cough (2; PHR; TRA; WAM; ZIM); Cramp (1; KOM; PIP); Croup (1; APA; WBB); Cystosis (f; CRC; JFM); Dermatosis (1; APA); Diabetes (1; APA; JFM; PHR; WBB); Diphtheria (f; WBB); Dysentery (1; APA; CRC); Dyspepsia (f; JFM); Enterosis (f; PHR); Fever (1; APA; BGB; CAN; CRC; JFM; PHR; WBB); Flu (2; PHR; TRA; VAG); Fungus (1; JBU); Gas (f; WBB); Gastrosis (f; CRC; JFM; PHR); Gingivosis (f; CRC; JFM; PHR); Headache (f; BGB); Hepatosis (f; CRC; JFM; PHR); Hoarseness (f; PHR); Hyperglycemia (1; HHB; PHR); Infection (1; APA; CRC; JBU); Inflammation (1; CRC; PHR); Insomnia (1; TRA); Laryngosis (f; CRC); Leprosy (f; CRC; WBB); Malaria (f; CRC; JFM; WBB); Measles (f; PHR); Miasma (f; CRC); Myalgia (1; APA); Mycosis (1; JBU); Nervousness (1; TRA); Neuralgia (f; PHR); Otosis (1; BGB); Pain (1; CRC; TRA); Pertussis (f; PHR); Pharyngosis (1; APA; BGB); Phthisis (f; CRC); Pulmonosis (1; CRC; JFM); Respirosis (2; KOM; PIP; TRA); Rheumatism (2 [EO topical]; JFM; KOM; PHR); Rhinosis (f; CRC); Ringworm (1; APA); Scarlet Fever (f; PHR); Sinusosis (1; PHR); Sore (1; APA; CRC; JFM); Sore Throat (1; APA; CRC); Spasm (f; CRC); Stomatosis (1; APA); Syncope (1; FNF); Tuberculosis (f; CRC); Tumor (1; APA); Vaginosis (f; CRC); Virus (1; APA; JBU; PHR); Water Retention (1; PHR); Worm (1; CRC; HHB; PHR; TRA; WBB); Wound (f; CRC).

CONTRAINDICATIONS, INTERACTIONS, AND SIDE EFFECTS (Duke, J. A et al., 2002)

CLASS 2D. Contraindicated in inflammatory diseases of the bile duct, GI tract, and liver. Do not use near nostrils of infants (AHP). CAN cautions that the oil can cause nausea and vomiting, and should not be taken internally during pregnancy or lactation. “Undiluted eucalyptus oil is toxic and should not be taken internally unless suitably diluted. A dose of 3.5 ml has proved fatal.” (CAN) Symptoms of poisoning include abdominal pain, bronchospasm, convulsions, cyanosis, delirium, dizziness, epigastric burning, myosis, muscular weakness, respiratory problems, spontaneous vomiting, tachypnea with severe respiratory depression, and a feeling of suffocation. May interfere with hypoglycemic therapy (CAN). Eucalyptus oil causes induction of the foreign-substance degrading enzyme system in the liver. This may weaken and/or shorten the activity of other medicinal agents; may cause diarrhea, nausea, and vomiting (PIP). CNS effects include diminution or loss of reflexes and depression of consciousness, possibly progressing to coma. Fatalities have been reported in adults ingesting as little as 4–5 ml eucalyptus oil; 30 ml will usually cause death (AEH1).

CONTRAINDICATIONS (Linda, S-R. 2010)

CLASS 2D HERB (LEAF).

Until more research is available, eucalyptus should not be used during pregnancy and breastfeeding. It should not be given to children younger than 2 years of age. Eucalyptus should not be used near mucous membranes or on the face. Persons with hypersensitivity to eucalyptus and those with kidney, gastrointestinal, or severehepatic disease should not use this herb. As  little as 3.5 ml of eucalyptus oil taken internally can be fatal.

CONTRAINDICATIONS AND PRECAUTIONS (Braun, L and Cohen, M. 2010)

Essential oils are not recommended in the first 3 months of life because the barrier function of the skin is not fully developed. In addition, inhaling menthol can induce transient apnoea in premature infants due to its effects on the TRPM 8 receptor (Javorka et al 1980); thus, essential oils containing 1,8-cineole should not be applied on or near the face of babies and small children. E. globulus may cause skin allergy in susceptible individuals (those prone to asthma and allergies, and with a previous reaction to eucalyptus).

Eucalyptus oil should not be administered internally to children or people with inflammatory gastrointestinal tract disease or impaired liver function, or during pregnancy. Eucalyptus oil should not be applied to the face, especially of infants and young children because of the risk of bronchospasm and irritation. The oil should be stored out of the reach of children and confused people. Vaporisers containing eucalyptus essential oils should also be placed out of reach. Poisoning has occurred following ingestion from vaporisers. Oily carrier fluids should not be used for nasal sprays because they inhibit protective nasal ciliary movements and could cause lipid pneumonia. The essential oil is highly flammable and represents a fire risk when used in candle vaporisers.

SIDE EFFECTS/ADVERSE REACTIONS (Linda, S-R. 2010)

CNS: Confusion, delirium, dizziness, seizures

GI: Burning stomach, nausea, vomiting, anorexia

INTEG: Hypersensitivity reactions

RESP: Bronchospasm

INTERACTIONS (Linda, S-R. 2010)

Drug

Amphetamines, barbiturates: Eucalyptus may decrease the effectiveness of amphetamines, barbiturates; avoid concurrent use.

Antidiabetics, insulin: Eucalyptus may alter the effectiveness of antidiabetics, insulin; do not use concurrently.

Herb

Basil, glucomannan, Queen Anne’s lace: These herbs may decrease blood glucose when used with eucalyptus (PO).

Lab Test

Blood glucose: Eucalyptus (PO) may decrease blood glucose levels.

SIGNIFICANT INTERACTIONS (Braun, L and Cohen, M. 2010)

Due to the lack of clinical evidence, interactions are theoretical and speculative.

CNS depressants

Oral ingestion of eucalyptus has been associated with CNS depression, therefore additive effects are theoretically possible —caution.

Drugs metabolised by CYP 450

Some evidence suggests CYP induction is possible; however, it is not known which CYP enzymes are affected, thus making recommendations difficult. Interactions are unlikely when used topically or inhaled, but could theoretically occur when used internally (Springhouse Corporation 2001).

Hypoglycaemic agents

If used in combination with oral glucose-lowering conventional or complementary medicines it may contribute to hypoglycaemia (oral doses) — blood glucose levels should be monitored (Springhouse Corporation 2001).

CLIENT CONSIDERATIONS (Linda, S-R. 2010)

Assess

•       Assess the reason the client is using eucalyptus.

•       Assess for hypersensitivity reactions. If present, discontinue use of eucalyptus and administer an antihistamine or other appropriate therapy.

•       Assess for central nervous system reactions if the client is taking this herb internally.

•       Assess for the use of amphetamines, barbiturates, insulin, and antidiabetics (see Interactions).

Administer

•       Instruct the client to store eucalyptus products in a cool, dry place, away from heat and moisture.

•       Instruct the client to dilute all products used internally before use.

Teach Client/Family

·      Caution the client not to use eucalyptus in children who are younger than 2 years of age or those who are pregnant or breastfeeding until more research is available.

·      Inform the client that eucalyptus may be used topically on children in combination with menthol and camphor.

·      Alert the client that poisoning of children has occurred with only a few drops of eucalyptus.

·      Caution clients with hypersensitivity to eucalyptus and those with renal, gastrointestinal, or severe hepatic disease not to use this herb.

·      Use extreme caution if taking internally.

TOXICITY (Braun, L and Cohen, M. 2010)

Toxicity symptoms occur rapidly, but may be delayed for hours and include altered conscious state, drowsiness and unconsciousness, which are dose-dependent. Symptoms reported in other studies include epigastric burning, nausea, vomiting, dizziness, muscular weakness, delirium and convulsions. The acute oral LD50 dose of 1,8-cineole in rats is 2.48 g/kg and the dermal LD50 dose in rabbits is > 5 g/kg.

Fatal poisoning has occurred in children after accidental ingestion of whole or diluted eucalyptus oil in amounts ranging from 2 to 10 mL. Tibballs (1995) reported 109 children who were admitted to hospital for eucalyptus oil poisoning in an 11-year period; 27 had been accidentally poisoned when an adult administered the oil orally by mistake and most of the remaining 82 children had ingested the oil from a vaporiser. Another review of 41 cases of eucalyptus oil poisoning (Webb & Pitt 1993) indicated that 80% were asymptomatic. There was no relationship between the amount of oil ingested and the presence and severity of symptoms. The Victorian Poisons Information Centre (see Appendix 3) recommends all patients who ingest ≥ 1 mL of eucalyptus oil be assessed in an emergency department. The centre attributes the toxicity to the cineole, terpene and phellandrene content and indicates that although hydrocyanic acid is only present in small amounts it may be responsible for most of the toxicity.

PREGNANCY USE (Braun, L and Cohen, M. 2010)

No studies have been undertaken. The essential oil is not teratogenic in animal studies, but doses of 500 mg/kg cross the placenta in large enough amounts to stimulate hepatic activity in rodents (Jori & Briatico 1973). Aromatherapists do not use eucalyptus essential oil during pregnancy, especially in the first trimester.

PATIENTS’ FAQs (Braun, L and Cohen, M. 2010)

What will this essential oil do for me?

Eucalyptus essential oil can be used in a vaporiser or on tissues to help clear the nose and make breathing easier in the presence of an URTI. It can also increase mental alertness. In a massage blend eucalyptus can help relieve muscular and arthritic pain. Eucalyptus oil can be added to the washing machine to help kill dust mites in human clothes and animal bedding. Dust mites are responsible for many respiratory conditions, such as asthma.

When will it start to work?

Inhaled eucalyptus oil usually acts quickly and provides symptomatic relief quickly. Oral doses and massage blends usually take longer to have an effect.

Are there any safety issues?

Ingested eucalyptus oil has caused poisoning especially in children and therefore any source of the oil, including vaporisers, should be placed out of reach. Eucalyptus can irritate the eyes and mucous membranes. It should be kept away from the face, especially of infants and children. Ingested eucalyptus oil could affect the action of some medicines such as antidepressants, sedatives and anaesthetic agents. It increases absorption of nicotine.

EXTRACTS (Duke, J. A et al., 2002)

In vivo, quercitrin and hyperoside have shown antiviral activity against influenza type A (CAN). Euglobulin reported to be antiinflammatory, antiproliferative, and to inhibit in vitro TPA-induced EBV-EA activity in animal studies (PHR). Cineole is antispasmodic, bactericide, fungicide, secretogogic, secretolytic, and rubefacient (SHT).

PRACTICE POINTS/PATIENT COUNSELLING (Braun, L and Cohen, M. 2010)

v Eucalyptus essential oils are steam distilled from a number of Eucalyptus species, and have different chemical compositions depending on the species. Most contain a large proportion of 1,8-cineole, which appears to be responsible for the action on the respiratory system.

v Eucalyptus is primarily used in aromatherapy as an inhalation to relieve nasal congestion and in massage to relieve muscular aches and pain, as well as in ointments, gels and compresses, and via a vaporiser for mental stimulation and to aid concentration.

v It is used internally in lozenges, tinctures and conventional medicines.

v When used topically in an appropriate manner, eucalyptus oil is considered safe; however, several cautions exist to reduce the risk of adverse reactions and toxicity. People using eucalyptus essential oil should be monitored for allergies and it should not be applied to the face of children. Eucalyptus should not be used internally unless it is diluted and used in the recommended doses and dose intervals.

v Signs of poisoning usually occur rapidly and include confusion, irritability, respiratory distress, hypotension, nausea and vomiting. If poisoning is suspected medical care should be sought urgently. Do not induce vomiting. Use charcoal and monitor consciousness.

v Several drug interactions are theoretically possible; however, their clinical significance is unknown.

REFERENCE

Barnes, J., Anderson, L. A., and Phillipson, J. D.  2007.  Herbal Medicines Third Edition. Pharmaceutical Press. Auckland and London.

Braun, L and Cohen, M. 2010. Hebs and Natural Supplements An Evidence Based Guide 3R D Edition. Elsevier Australia. Australia.

Chevallier, A. 2018. Herbal Remedies Handbook. DK Publishing. New York.

Duke, J. A. with Mary Jo Bogenschutz-Godwin, Judi duCellier, Peggy-Ann K. Duke. 2002.  Handbook of Medicinal Herbs 2nd Ed. CRC Press LLC. USA.

Kraft, K and Hobbs, C. 2004 . Pocket Guide to Herbal Medicine. Thieme. Stuttgart New York.

Linda S-Roth. 2010. Mosby’s Handbook Of Herbs & Natural Supplements, Fourth Edition. Mosby Elsevier. USA.

Ross, I. A. 2001. Medicinal Plants of the World Vol. 2. Chemical Constituents, Traditional and Modern Medical Uses. Human Press. Totowa, New Jersey.

Eucalyptus_bicostata_plant (wtlandcare.org)