Author(s): Tatsuru Kitamura and Shoryoku Hino
Neuropsychiatric adverse events related to the long-term use of donepezil are not well known. Herein we report on two very elderly patients with Alzheimer’s disease in whom Disinhibition occurred after at least 5 years of oral donepezil.
Neither of the two patients (one an 88-year-old woman and the other a 98-year-old woman) had a history of preexisting psychiatric disorder, and no adverse events had been noted after starting donepezil prior to the development of Disinhibition. After discontinuation of donepezil, Disinhibition resolved within 1-2 months, during which time there were no physical, environmental, or other prescription changes.
A causal relationship between donepezil and Disinhibition was considered to be present. There have been no reports of Disinhibition associated with donepezil use in patients with Alzheimer’s disease. As we enter into a superaging society, further studies are needed to determine how long donepezil should be administered.
