Aromatherapy

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Aromatherapy is a form of alternative medicine that uses volatile liquid plant materials, known as essential oils (EOs), and other aromatic compounds from plants for the purpose of affecting a person's mood or health. Essential oils differ in chemical composition from other herbal products because the distillation process only recovers the lighter phytomolecules. For this reason essential oils are rich in monoterpenes and sesquiterpenes, as well as other VOC substances (esters, aromatic compounds, non-terpene hydrocarbons, some organic sulfides etc.).

Aromatherapy is a generic term that refers to any of the various traditions that make use of essential oils sometimes in combination with other alternative medical practices and spiritual beliefs. Popular use of these products include massaging products, medicine, or any topical application that incorporates the use of essential oils to their products.^[1] It has a particularly Western currency and persuasion. Medical treatment involving aromatic compounds may exist outside of the West, but may or may not be included in the term 'aromatherapy'.

Contents 1 History 2 Modes of application 3 Materials 4 Theory 5 Choice and purchase 6 Price 7 Pharmacological effects attributed to essential oils 8 Popular uses 9 Efficacy 10 Safety concerns 11 References 11.1 Journals 12 External links 13 Criticism 14 Further reading

[edit] History

Aromatherapy had been around for 6000 years or more. The Greeks, Romans, and ancient Egyptians all used aromatherapy oils. The Egyptian physician Imhotep recommended fragrant oils for bathing, massage, and for embalming their dead nearly 6000 years ago. Imhotep is the Egyptian god of medicine and healing. Hippocrates, the father of modern medicine, used aromatherapy baths and scented massage. He used aromatic fumigations to rid Athens of the plague.

Aromatherapy has roots in antiquity with the use of aromatic oils. However, as currently defined, aromatherapy involves the use of distilled plant volatiles, a twentieth century innovation. The word "aromatherapy" was first used in the 1920s by French chemist René-Maurice Gattefossé, who devoted his life to researching the healing properties of essential oils after an accident in his perfume laboratory. In the accident, he set his arm on fire and thrust it into the nearest cold liquid, which happened to be a vat of NOx Ph232 or more commonly known as lavender oil. Immediately he noticed surprising pain relief, and instead of requiring the extended healing process he had experienced during recovery from previous burns—which caused redness, heat, inflammation, blisters, and scarring--this burn healed remarkably quickly, with minimal discomfort and no scarring. Jean Valnet continued the work of Gattefossé. During World War II Valnet used essential oils to treat gangrene in wounded soldiers.

[edit] Modes of application

The modes of application of aromatherapy include:

• aerial diffusion for environmental fragrancing or aerial disinfection
• direct inhalation for respiratory disinfection, decongestion, expectoration as well as psychological effects
• topical applications for general massage, baths, compresses, therapeutic skin care
• oral, rectal, vaginal interfaces for infection, congestion, parasites, perfumery for body fragrancing, anointments

[edit] Materials

Some of the materials employed include:

• Essential oils: Fragrant oils extracted from plants chiefly through steam distillation (e.g. eucalyptus oil) or expression (grapefruit oil). However, the term is also occasionally used to describe fragrant oils extracted from plant material by any solvent extraction.
• Absolutes: Fragrant oils extracted primarily from flowers or delicate plant tissues through solvent or supercritical fluid extraction (e.g. rose absolute). The term is also used to describe oils extracted from fragrant butters, concretes, and enfleurage pommades using ethanol.
• Phytoncides: Various volatile organic compounds from plants that kill microbes. Many terpene-based fragrant oils and sulfuric compounds from plants in the genus "Allium" are phytoncides, though the latter are likely less commonly used in aromatherapy due to their disagreeable odors.
• Herbal distillates or hydrosols: The aqueous by-products of the distillation process (e.g. rosewater). There are many herbs that make herbal distillates and they have culinary uses, medicinal uses and skin care uses. Common herbal distillates are rose, lemon balm and chamomile.
• Infusions: Aqueous extracts of various plant material (e.g. infusion of chamomile)
• Carrier oils: Typically oily plant base triacylglycerides that dilute essential oils for use on the skin (e.g. sweet almond oil)

[edit] Theory

The neutrality of this section is disputed. Please see the discussion on the talk page.(December 2007) Please do not remove this message until the dispute is resolved.

Aromatherapy is the treatment or prevention of disease by use of essential oils. Two basic mechanisms are offered to explain the purported effects. One is the influence of aroma on the brain, especially the limbic system through the olfactory system. The other is the direct pharmacological effects of the essential oils^[2]. While precise knowledge of the synergy between the body and aromatic oils is often claimed by aromatherapists, the efficacy of aromatherapy remains to be proven. However, some preliminary clinical studies show positive effects. ^{[3] [4]}

In the English-speaking world, practitioners tend to emphasize the use of oils in massage. Aromatherapy tends to be regarded as a complementary modality at best and a pseudoscientific fraud at worst.^[5]

On the continent, especially in France, where it originated, aromatherapy is incorporated into mainstream medicine. There, the use of the antiseptic, antiviral, antifungal, and antibacterial properties of oils in the control of infections is emphasized over the approaches familiar to North Americans. In France some essential oils are regulated as prescription drugs, and thus administered by a physician. French doctors use a technique called the aromatogram to guide their decision on which essential oil to use. First the doctor cultures a sample of infected tissue or secretion from the patient. Next the growing culture is divided among petri dishes supplied with agar. Each petri dish is inoculated with a different essential oil to determine which have the most activity against the target strain of microorganism. The antiseptic activity manifests as a pattern of inhibited growth.^[6][7]

In many countries essential oils are included in the national pharmacopoeia, but up to the present moment aromatherapy as science has never been recognized as a valid branch of medicine in the United States, Russia, Germany, or Japan.

Essential oils, phytoncides and other natural VOCs work in different ways. At the scent level they activate the limbic system and emotional centers of the brain. When applied to the skin (commonly in form of "massage oils" i.e. 1-10% solutions of EO in carrier oil) they activate thermal receptors, and kill microbes and fungi. Internal application of essential oil preparations (mainly in pharmacological drugs; generally not recommended for home use apart from dilution - 1-5% in fats or mineral oils, or hydrosoles) may stimulate the immune system.

[edit] Choice and purchase

Oils with standarized content of components (marked FCC, for Food Chemical Codex) have to contain a specified amount of certain aroma chemicals that normally occur in the oil. But there is no law that the chemicals cannot be added in synthetic form in order to meet the criteria established by the FCC for that oil. For instance, lemongrass essential oil has to contain 75% aldehyde to meet the FCC profile for that oil, but that aldehyde can come from a chemical refinery instead of from lemongrass. To say that FCC oils are "food grade" then makes them seem natural when in fact they are not necessarily so.

Undiluted essential oils suitable for aromatherapy are termed therapeutic grade, but in countries where the industry is not regulated, therapeutic grade is based on industry consensus and is not a regulatory category. Some aromatherapists take advantage of this situation to make misleading claims about the origin and even content of the oils they use. Likewise, claims that an oil's purity is vetted by mass spectrometry or gas chromatography have limited value, since all such testing can do is show that various chemicals occur in the oil. Many of the chemicals that occur naturally in essential oils are manufactured by the perfume industry and adulterate essential oils because they are cheaper. There is no way to distinguish between these synthetic additives and the naturally occurring chemicals.

The best instrument for determining whether an essential oil is adulterated is an educated nose. Many people can distinguish between natural and synthetic scents, but it takes experience.

[edit] Price

Oils vary in price based on the amount of the harvest, the country of origin, the type of extraction used (steam distillation, CO₂ extract, enfleurage), and how desirable the oil is. Indian Sandalwood (Santalum album) is considered more desirable than Australian Sandalwood (Santalum spicatum), based upon the aroma, and is twice as costly, mainly because the species that yields Indian Sandalwood essential oils is endangered. Organic and wild harvested essential oils also tend to be more expensive.

[edit] Pharmacological effects attributed to essential oils

• antibacterial In vitro testing has confirmed antibacterial effects in certain oils including rosemary, clove, lime, cinnamon, and tea tree oil.^{[8][9][10][11]}
• antiviral Supported for tea tree oil, lemongrass, sandlewood, peppermint, ginger, thyme, and hyssop in in vitro testing against Herpes^{[12][13][14][15][16]}
• antifungal Supported by in vitro testing for lavender, thyme, clove, juniper, and tea tree oil^{[17][18][19][20][21]}
• anti-inflammatory Reported in in-vitro assays of clove, cinnamon, sage, eucalyptus, black cumin and bay leaf^{[22][23][24][25][26][27]}
• anxiolytic Reported in animal models using oils of lavender, rose and angelica ^[28][29][30]
• antispasmotic
• invigorating
• antioxidant

[edit] Popular uses

• Basil is used in perfumery for its clear, sweet and mildly spicy aroma. In aromatherapy, it is used for sharpening concentration, for its uplifting effect on depression, and to relieve headaches and migraines. Basil oil has many chemotypes and some are known to be emmenagogues and should be avoided during pregnancy.

• Bergamot is one of the most popular oils in perfumery. It is an excellent insect repellent and may be helpful for both the urinary tract and for the digestive tract. It is useful for skin conditions linked to stress, such as cold sores and chicken pox, especially when combined with eucalyptus oil. Bergamot is a flavoring agent in Earl Grey tea. But cold-pressed Bergamot oil contains bergaptene, a strong photosensitizer when applied to the skin, so only distilled or 'bergaptene-free' types can be topically used.

• Black pepper has a sharp and spicy aroma. Common uses include stimulating the circulation and for muscular aches and pains. Skin application is useful for bruises, since it stimulates the circulation.

• Citronella oil, obtained from a relative of lemongrass, is used as an insect repellent and in perfumery.

• Clove oil is a topical analgesic, especially useful in dentistry. It is also used an antiseptic, antispasmodic, carminative, and antiemetic.

• Eucalyptus oil is often used in combination with peppermint to provide relief for the airways in case of cold or flu.

• Geranium oil is used as an astringent, antiseptic and diuretic.

• Jasmine is used as an aphrodisiac

• Lavender oil is used as an antiseptic, to soothe minor cuts and burns, to calm and relax, and to soothe headaches and migraines.

• Lemon oil is uplifting and anti-stress/anti-depressant. In a Japanese study, lemon essential oil in vapour form has been found to reduce stress in mice.^[31]

• Lemon oil - Researchers at Ohio State University reveals that Lemon oil aroma may enhance your mood, and may relax you.

• Rose is used as an aphrodisiac

• Sandalwood oil is used as an aphrodisiac

• Tea tree oil and many other essential oils have topical (external) antimicrobial (i.e. antibacterial, antifungal, antiviral, or antiparasitic) activity and are used as antiseptics and disinfectants.^[32]

• Thyme oil^[33]

• Yarrow oil is used to reduce joint inflammation and relieve cold and influenza symptoms.

• Ylang-ylang oil is used as an aphrodisiac

[edit] Efficacy

The consensus among most medical professionals is that while pleasant scents can boost relaxation and may have related benefits for patients, there is currently insufficient scientific proof of the effectiveness of aromatherapy in general.^[34] Scientific research on the cause and effect of aromatherapy is limited, although in vitro testing has revealed some antibacterial and antiviral effects and a few double blind studies have been published.^[35][36]

Like many alternative therapies, few controlled, double-blind studies have been carried out—a common explanation is that there is little incentive to do so if the results of the studies are not patentable. Researchers at Sloan-Kettering have found that aromatherapy significantly reduces claustrophobia attacks for patients undergoing MRI scans; however, studies of similar rigor are far from numerous. Some benefits that have been linked to aromatherapy, such as relaxation and clarity of mind, may arise from the placebo effect rather than from the inherent properties of the scents themselves.

Skeptical literature suggests that aromatherapy is based on the anecdotal evidence of its benefits rather than proof that aromatherapy can cure diseases. Scientists and medical professionals acknowledge that aromatherapy has limited scientific support, but critics argue that the claims of most aromatherapy practitioners go beyond the data, and/or that the studies are neither adequately controlled nor peer reviewed.

Customers should be aware that aromatherapy may be unregulated, depending on the country. The term "aromatherapy" has been applied to such a wide range of products that many are labeled "aromatherapy" products simply because they contain essential oils, although they may provide no therapeutic benefit.

Some proponents of aromatherapy believe that the claimed effect of each type of oil is not caused by the chemicals in the oil interacting with the senses, but because the oil contains a distillation of the "life force" of the plant from which it is derived that will "balance the energies" of the body and promote healing or well-being by purging negative vibrations from the body's energy field. Arguing that there is no scientific evidence that healing can be achieved, and that the claimed "energies" even exist, many skeptics reject this form of aromatherapy as pseudoscience or even quackery.

[edit] Safety concerns

In addition, there are potential safety concerns. Because essential oils are highly concentrated they can irritate the skin when used neat. As such, they are normally diluted with a carrier oil for topical application. Phototoxic reactions may occur with citrus peel oils such as lemon or lime ^[37]. Also, many essential oils have chemical components that are sensitisers (meaning that they will after a number of uses cause reactions on the skin, and more so in the rest of the body). Some oils can be toxic to some domestic animals, with cats being particularly prone.^[38][39]

Two common oils, lavender and tea tree, have been implicated in causing gynaecomastia, an abnormal breast tissue growth, in prepubescent boys. ^[40] A child hormone specialist at the University of Cambridge claimed "... these oils can mimic oestrogens" and "people should be a little bit careful about using these products". ^[41]

As with any bioactive substance, an essential oil that may be safe for the general public could still pose hazards for pregnant and lactating women.

While some advocate the ingestion of essential oils for therapeutic purposes, licensed aromatherapy professionals do not recommend self prescription due the highly toxic nature of some essential oil. Some very common oils like Eucalyptus are extremely toxic when taken internally. Doses as low as one teaspoon has been reported to cause clinically significant symptoms and severe poisoning can occur after ingestion of 4 to 5 ml.^[42] A few reported cases of toxic reactions like liver damage and seizures have occurred after ingestion of sage, hyssop, thuja, and cedar.^[43] Accidental ingestion may happen when oils are not kept out of reach of children.

Oils both ingested and applied to the skin can potentially have negative interaction with conventional medicine. For example, the topical use of methyl salicylate heavy oils like Sweet Birch and Wintergreen may cause hemorrhaging in users taking the anticoagulant Warfarin.

Adulterated oils may also pose problems depending on the type of substance used.

[edit] References

1. ^ "Making Scents: Aromatherapy and the Benefits of Essential Oils" Sfbsc.com
2. ^ Seenivasan Prabuseenivasan , Manickkam Jayakumar and Savarimuthu Ignacimuthu (2006). "In vitro antibacterial activity of some plant essential oils". BMC Complementary and Alternative Medicine 6 (39). doi:10.1186/1472-6882-6-39. 
3. ^ Kim HJ (Jun 2007). "Effect of Aromatherapy Massage on Abdominal Fat and Body Image in Post-menopausal Women." (in Korean). Taehan Kanho Hakhoe Chi 37 (4): 603–12. PMID 17615482. 
4. ^ Rho KH, Han SH, Kim KS, Lee MS. (Dec 2006). "Effects of aromatherapy massage on anxiety and self-esteem in korean elderly women: a pilot study". Int J Neurosci 116 (12): 1447–55. PMID 17145679. 
5. ^ Aromatherapy
6. ^ http://www.florihana.com/en/aromatogram.htm The Aromatogram
7. ^ http://www.pranarom.co.uk/en/essential_oil/aromatogramme Aromatogram
8. ^ "Screening of the antibacterial effects of a variety of essential oils on microorganisms responsible for respiratory infections." (April, 2007). Phytother Res. 21 (4): 374–7. PMID 17326042. 
9. ^ "Potential of rosemary oil to be used in drug-resistant infections." (Sept-Oct 2007). Altern Ther Health Med. 13 (5): 54–9. PMID 17900043. 
10. ^ "In vitro antibacterial activity of some plant essential oils." (Nov 30, 2006). BMC Complement Altern Med. 2006 Nov 30;6:39 6 (39). PMID 17134518. 
11. ^ "Melaleuca alternifolia essential oil possesses potent anti-staphylococcal activity extended to strains resistant to antibiotics." (2006 Jul-Sep). Int J Immunopathol Pharmacol.;19(3):. 19 (3): 539–44. PMID 17026838. 
12. ^ "Susceptibility of drug-resistant clinical herpes simplex virus type 1 strains to essential oils of ginger, thyme, hyssop, and sandalwood." (2007 May). Antimicrob Agents Chemother. 51 (5): 1859–62. PMID 17353250. 
13. ^ "Virucidal effect of peppermint oil on the enveloped viruses herpes simplex virus type 1 and type 2 in vitro." (2003). Phytomedicine 10 (6-7): 504–10. PMID 13678235. 
14. ^ "The inhibitory effect of essential oils on herpes simplex virus type-1 replication in vitro." (2003). Microbiol Immunol. 47 (9): 681–4. PMID 14584615. 
15. ^ "Antiviral activity of sandalwood oil against herpes simplex viruses-1 and -2." (1999 May). Phytomedicine. 6 (2): 119–23. PMID 10374251. 
16. ^ "Antiviral activity of the volatile oils of Melissa officinalis L. against Herpes simplex virus type-2." (2004 Nov). Phytomedicine. 11 (7-8): 657–61. PMID 15636181. 
17. ^ { "Antioxidant properties of the essential oil of Eugenia caryophyllata and its antifungal activity against a large number of clinical Candida species." (2007 Sep). Mycoses. 50 (5): 403–6. PMID 17714361. 
18. ^ "Antifungal activity of the essential oil of Thymus pulegioides on Candida, Aspergillus and dermatophyte species." (2006 Oct). J Med Microbiol. 55 (Pt 10): 1367–73. PMID 17005785. 
19. ^ "Antifungal activity of the essential oil of Melaleuca alternifolia (tea tree oil) against pathogenic fungi in vitro." (1996). Skin Pharmacol. 9 (6): 388–94. PMID 9055360. 
20. ^ "Antifungal activity of Juniperus essential oils against dermatophyte, Aspergillus and Candida strains." (2006 Jun). J Appl Microbiol. 100 (6): 1333–8. PMID 16696681. 
21. ^ "Antifungal activity of Lavandula angustifolia essential oil against Candida albicans yeast and mycelial form." (2005 Aug). Med Mycol. 43 (5): 391–6. PMID 16178366. 
22. ^ "Effects of Salvia officinalis L. extract on experimental acute inflammation." (2007 Jan-Mar). Rev Med Chir Soc Med Nat Iasi. 111 (1): 290–4. PMID 17595884. 
23. ^ "The chemical composition and biological activity of clove essential oil, Eugenia caryophyllata (Syzigium aromaticum L. Myrtaceae): a short review." (2007 Jun). Phytother Res. 21 (6): 501–6. PMID 17380552. 
24. ^ "Analgesic and anti-inflammatory effects of essential oils of Eucalyptus." (2003 Dec). J Ethnopharmacol. 89 (2-3): 277–83. PMID 14611892. 
25. ^ "Study on the antiinflammatory activity of essential oil from leaves of Cinnamomum osmophloeum." (2005 Sep 7). J Agric Food Chem. 53 (18): 7274–8. PMID 16131142. 
26. ^ "Black cumin seed essential oil, as a potent analgesic and antiinflammatory drug." (2004 Mar). Phytother Res. 18 (3): 195–9. PMID 15103664. 
27. ^ "Analgesic and anti-inflammatory activity of the leaf essential oil of Laurus nobilis Linn." (2003 Aug). Phytother Res.;(7): 17 (7): 733–6. PMID 12916069. 
28. ^ "Anxiolytic effects of lavender oil inhalation on open-field behaviour in rats." (2007 Sep Epub 2007 May 4). Phytomedicine 14 (9): 613–20. PMID 17482442. 
29. ^ "Anxiolytic-like effects of rose oil inhalation on the elevated plus-maze test in rats." (2004 Feb). Pharmacol Biochem Behav.;(): 77 (2): 361–4. PMID 14751465. 
30. ^ "The effects of angelica essential oil in three murine tests of anxiety." (2004 Oct). Pharmacol Biochem Behav. 79 (2): 377–82. PMID 15501315. 
31. ^ Lemon oil vapor causes an anti-stress effect via modulating the 5-HT and DA activities in mice.. PubMed.gov (2006-06-15). Retrieved on 2007-04-26.
32. ^ http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=AbstractPlus&list_uids=16161028&query_hl=1&itool=pubmed_DocSum][1] Antibacterial activity of essential oils from Australian native plants.
33. ^ http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=AbstractPlus&list_uids=16690225&query_hl=14&itool=pubmed_docsum Antimicrobial and antiplasmid activities of essential oils.
34. ^ http://www.cancer.gov/cancertopics/pdq/cam/aromatherapy/HealthProfessional/page3 Aromatherapy and Essential Oils
35. ^ Ballard CG, O'Brien JT, Reichelt K, Perry EK (2002). "Aromatherapy as a safe and effective treatment for the management of agitation in severe dementia: the results of a double-blind, placebo-controlled trial with Melissa.". J Clin Psychiatry 63 (7): 553–8. PMID 12143909. 
36. ^ Holmes C, Hopkins V, Hensford C, MacLaughlin V, Wilkinson D, Rosenvinge H. (Apr 2002). "Lavender oil as a treatment for agitated behaviour in severe dementia: a placebo controlled study.". Int J Geriatr Psychiatry 17 (4): 305–8.. PMID 11994882. 
37. ^ http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1312240 Hyperpigmented macules and streaks
38. ^ The Lavender Cat - Cats and Essential Oil Safety
39. ^ K. Bischoff, F. Guale (1998). "Australian tea tree (Melaleuca alternifolia) Oil Poisoning in three purebred cats" (^{[dead link]} – ^{Scholar search}). Journal of Veterinary Diagnostic Investigation 10 (108). 
40. ^ Henley, D. V. (2007). "Prepubertal gynecomastia linked to lavender and tea tree oils". New England Journal of Medicine 356 (5): 479–85. doi:10.1056/NEJMoa064725. PMID 17267908. 
41. ^ "Oils make male breasts develop", BBC News, February 1, 2007. Retrieved on 2007-09-09. 
42. ^ Eucalyptus oil (PIM 031)
43. ^ Millet Y, Jouglard J, Steinmetz MD, Tognetti P, Joanny P, Arditti J. (Dec 1981). "Toxicity of some essential plant oils. Clinical and experimental study.". Clin Toxicol. 18 (12): 1485–98. PMID 7333081. 

[edit] Journals

• Aromatherapy Journal
• International Journal of Aromatherapy
• Aroma Scents Journal

[edit] External links

• The National Association for Holistic Aromatherapy
• International Federation of Aromatherapy
• Aromatherapy : a healing art
• Official Website of a medical grade herb vaporizer
• Essential oil and Aromatherapy (fr. with translator)
• The History of Aromatherapy
• Aromatherapy Guide
• Aromatherapy: What Is It?
• Aromatherapy and Essential Oil Cautions and Safety Information
• What Does the Research Say About Essential Oils?
• Antiviral and Antimicrobial Properties of Essential Oils
• The Aromatherapy Global Online Research Archives

[edit] Criticism

• Smell Research by Tim Jacob: Aromatherapy - does it work?
• Aromatherapy: Making Dollars out of Scents

[edit] Further reading

• Maria Lis-Balchin, Aromatherapy science - a guide for healthcare professionals, éd. Pharmaceutical Press (2006)
• Kurt Schnaubelt, Ph.D., Advanced Aromatherapy : The Science of Essential Oil Therapy, (ISBN 0-89281-743-7)
• Kurt Schnaubelt, Ph.D., Medical Aromatherapy : Healing With Essential Oils (ISBN 1-883319-69-2)
• The Practice of Aromatherapy: A Classic Compendium of Plant Medicines and Their Healing Properties (ISBN 0-89281-398-9)
• National Research Council (2003). Food Chemicals Codex. National Academy Press. ISBN 0309088666. 
• Christopher Wanjek, Bad Medicine : Misconceptions and Misuses Revealed, from Distance Healing to Vitamin O, John Wiley and Sons, Inc. (ISBN 0-471-43499-X)
• Dr. Jean Valnet, The Practice of Aromatherapy (ISBN 0852071434)