Essential oils in the treatment of Alzheimer’s disease and dementia

Alzheimer’s disease is a progressive, degenerative disease of the brain, which causes thinking and memory to become seriously impaired. It is the most common form of dementia. Dementia is a syndrome consisting of a number of symptoms that include loss of memory, judgment and reasoning, and changes in mood, behaviour and communication abilities.1

There has been research to support the use of essential oils for aiding with cognitive function, agitation, behavioural issues, aggressiveness, memory enhancement and mood. Essential oils such as rosemary (Rosmarinum off. verbenon), peppermint (Mentha piperita) and lemon (Citrus limonum) are known to enhance memory and alertness. Oils such as lavender (Lavandula angustifolia), orange (citrus senensis) and ylang ylang (Cananga odorata) are known for their sedative, calming and antidepressant properties.2 To increase alertness, I recommend oils such as rosemary, basil (Ocimum basilicum), peppermint and lemon. Oils to aid with sleep and restlessness include lavender, Roman chamomile (Anthemis nobilis), neroli (Citrus aurantium amara) and mandarin (Citrus reticulata).

Also, research has shown that although there is an olfactory dysfunction in people with Alzheimer’s disease (AD), the loss of one’s sense of smell does not affect the essential oils effectiveness, as they work at a physiological level. The oils are inhaled through and absorbed by the lungs and through the skin and are effective due to their chemical make up. It is believed that the loss of smell may be an early sign of Alzheimer’s and other neurodegenerative diseases.

One of the most popular essential oils and one shown to be beneficial with Alzheimer’s, is lavender. A hand massage with lavender essential oil has shown to help with emotions and reduce aggressive behaviour in elderly with Alzheimer’s type dementia.3

In another study, lavender and orange were used in the evening, and rosemary and lemon used during the day with 28 patients with dementia, of which 17 had AD. All patients showed significant improvement in orientation related to cognitive function. Laboratory tests after this study showed that there were no side effects with the use of aromatherapy.4

Acetylcholinesterase, aka AChE, is the main target for many drugs to treat AD and dementia. AChE is an enzyme, which degrades the neurotransmitter acetylcholine. Thyme (Thymus vulgaris) essential oil and its compounds, thymol, linalool and carvacrol, were found inhibit AChE.5

In a placebo controlled, double blind study, sage (Salvia officinalis) and Spanish sage (Salvia lavandulaefolia) have shown to increase the speed of memory and enhance mood.6 An earlier study showed that Spanish sage inhibits the enzyme acetylcholinesterase (AChE).7 Black pine (Pinus nigra) has also shown to have AChE and butyrylcholinesterase (BChE) inhibitory activity.8

Another placebo controlled trial with lemon balm (Melissa officinalis) was conducted in a health care facility to assess treatment for agitation in patients with severe dementia. Sixty percent of the active group showed a 30% decrease of their CMAI agitation (Cohen-Mansfield Agitation Inventory) score.9

Some people who suffer from AD and other forms of dementia, experience Sundowner’s Symdrome, named so as these confusion symptoms appear after ‘sundown’. These symptoms can include restlessness, wandering, depression, agitation and hallucinations. Many of the essential oils mentioned can be used to aid with these symptoms.

Applications, which have been used successfully in nursing homes and at home, include inhalation of the essential oil, a room spray made with the appropriate hydrosols, use of the essential oils in a diffuser, adding a few drops to a bath or onto a pillow and a custom made inhaler for personal use. As more research and clinical trials are completed, aromatherapy (essential oil therapy) will become more recognized as an accepted and evidence based alternative to pharmaceutical drugs.

For those of you who have a family member with AD or are caring for one, there is an amount of stress involved in caring for your loved one and a feeling of helplessness. There are a number of essential oils to aid with stress, depression, anxiety and panic attacks.

Michelle Reynolds, CAHP

1. Alzheimer Society http://www.alzheimer.ca
2. Modulation of cognitive performance and mood by aromas of peppermint and ylang-ylang. Moss M, Hewitt S, Moss L, Wesnes K. Int J Neurosci. 2008 Jan;118(1):59-77. PMID: 18041606
3. The effect of lavender aromatherapy on cognitive function, emotion, and aggressive behavior of elderly with dementia. Lee SY. Taehan Kanho Hakhoe Chi. 2005 Apr;35(2):303-12. PMID:15860944
4. Effect of aromatherapy on patients with Alzheimer’s disease. Jimbo, D. Kimura, Y. Taniguchi, M. Inoue, M. Urakami, K. Psychogeriatrics. 2009 Dec;9(4):173-9. PMID: 20377818
5. In vitro acetylcholinesterase inhibitory properties of thymol, carvacrol and their derivatives thymoquinone and thymohydroquinone. Jukic M, Politeo O, Maksimovic M, Milos M, Milos M. Phytother Res. 2007 Mar;21(3):259-61. PMID: 17186491
6. Positive modulation of mood and cognitive performance following administration of acute doses of Salvia lavandulaefolia essential oil to healthy young volunteers. Tildesley NT, Kennedy DO, Perry EK, Ballard CG, Wesnes KA, Scholey AB. Physiol Behav. 2005 Jan 17;83(5):699-709. PMID: 15639154
7. In-vitro activity of S. lavandulaefolia (Spanish sage) relevant to treatment of Alzheimer’s disease. Perry NS, Houghton PJ, Sampson J, Theobald AE, Hart S, Lis-Balchin M, Hoult JR, Evans P, Jenner P, Milligan S, Perry EK. J Pharm Pharmacol. 2001 Oct;53(10):1347-56. PMID: 11697542
8. Acetylcholinesterase and butyrylcholinesterase inhibitory activity of Pinus species essential oils and their constituents. Bonesi M, Menichini F, Tundis R, Loizzo MR, Conforti F, Passalacqua NG, Statti GA, Menichini F. J Enzyme Inhib Med Chem. 2010 Oct;25(5):622-8. PMID: 20429778
9. 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. Ballard CG, O’Brien JT, Reichelt K, Perry EK. J Clin Psychiatry. 2003 Jun;64(6):732; author reply 732. PMID: 12143909