Numerous studies on the topical antibacterial effects of essential oils have been published; most have found the oils to have significant antimicrobial activity. Some essential oils are antiviral and inhibit replication of the herpes simplex virus. Other essential oils are fungistatic and fungicidal against both vaginal and oropharyngeal Candida albicans.
Studies on rats in Europe and Japan have shown that exposure to various odors can result in stimulation or sedation, as well as changes in behavioral responses to stress and pain. A study  on the sedative effects of essential oils and other fragrance compounds (mostly individual chemical components of the oils) on rat motility showed that lavender oil (Lavandula angustifolia Miller [synonyms: Lavandula spicata L.; Lavandula vera DC.]) in particular had a significant sedative effect, and several single-oil constituents (as opposed to whole essential oils) had similarly strong effects. The authors do not comment on the presumed mechanism for this effect, though they suggest that the difference in results between the different oils (some of which were found to be stimulating, some sedative) is related to the "different chemical structures of the compounds…and functional groups…indicating the essential role of the volatility of the fragrance compounds and its bioavailability." The differences in bioavailability are ascribed to different levels of lipophilia, with the more lipophilic oils producing the most sedative effects. The researchers also found significant plasma levels of the fragrance compounds after inhalation, suggesting that the effects of aromatherapy result from a direct pharmacological interaction rather than an indirect central nervous system relay.
Complementary and alternative medicine (CAM) is a group of diverse medical and health care systems, practices, and products that are not presently considered to be part of conventional medicine (see Question 1).
It is important that the same scientific evaluation that is used to assess conventional approaches be used to evaluate CAM therapies (see Question 4).
The National Cancer Institute and the National Center for Complementary and Alternative Medicine are sponsoring or cosponsoring...
Other studies have investigated the effects of aromatherapy on rats' behavioral and immunological responses to painful, stressful, or startling stimuli. In two European studies, rats exposed to pleasant odors during painful stimuli exhibited decreased pain-related behaviors, with some variation in response between the sexes.[5,6] Two studies from Japan showed an improvement in immunological and behavioral markers in rats exposed to fragrances while under stressful conditions.[7,8]
Aridoğan BC, Baydar H, Kaya S, et al.: Antimicrobial activity and chemical composition of some essential oils. Arch Pharm Res 25 (6): 860-4, 2002.
Minami M, Kita M, Nakaya T, et al.: The inhibitory effect of essential oils on herpes simplex virus type-1 replication in vitro. Microbiol Immunol 47 (9): 681-4, 2003.
D'Auria FD, Tecca M, Strippoli V, et al.: Antifungal activity of Lavandula angustifolia essential oil against Candida albicans yeast and mycelial form. Med Mycol 43 (5): 391-6, 2005.
Buchbauer G, Jirovetz L, Jäger W, et al.: Fragrance compounds and essential oils with sedative effects upon inhalation. J Pharm Sci 82 (6): 660-4, 1993.
Aloisi AM, Ceccarelli I, Masi F, et al.: Effects of the essential oil from citrus lemon in male and female rats exposed to a persistent painful stimulation. Behav Brain Res 136 (1): 127-35, 2002.
Jahangeer AC, Mellier D, Caston J: Influence of olfactory stimulation on nociceptive behavior in mice. Physiol Behav 62 (2): 359-66, 1997.
Shibata H, Fujiwara R, Iwamoto M, et al.: Immunological and behavioral effects of fragrance in mice. Int J Neurosci 57 (1-2): 151-9, 1991.
Fujiwara R, Komori T, Noda Y, et al.: Effects of a long-term inhalation of fragrances on the stress-induced immunosuppression in mice. Neuroimmunomodulation 5 (6): 318-22, 1998 Nov-Dec.
In this article
This information is produced and provided by the National
Institute (NCI). The information in this topic may have changed since it was written. For the most current information, contact the National
Institute via the Internet web site at http://
.gov or call 1-800-4-CANCER.
WebMD Public Information from the National Cancer Institute
September 04, 2014
This information is not intended to replace the advice of a doctor.
Healthwise disclaims any liability for the decisions you make based on this