Alzheimer‘s disease is the most common agerelated neurodegenerative disease. The current treatment objectives for dementia are mainly to suppress the progression of dementia and to treat BPSD such as hallucinations symptomatically. Clinicians aim to reduce the dose as much as possible because drug therapy always has problems of limited effects and side effects, and also problems of polypharmacy.
On the other hand, spatial memory and ability of discriminating smells are correlated, and the sense of smell is important for establishing spatial memory. Smell promotes appetite and improves memory and learning through ghrelin. This may be one of the rationale for the effectiveness of aromatherapy for dementia. Nose is not only the start point of smell sensation, but also a transporting route to the brain. There are several aroma oils that are said to be good for dementia. Thus, the sense of smell and nose using aroma oil will become more important in the future as a route for early diagnosis of dementia and development of the preventive and therapeutic measure. 
Aromatherapy using essential oils is one of the complementary therapies that fills the gap between such drug treatments in the treatment of dementia. 
In this symposium, I would review essential oils that are used complementarily for the treatment of dementia and consider their purpose and usage.