The six patients reported previously who developed mania with donepezil ranged in age from 50 to 78. Four were women; five carried diagnoses of dementia; and one had cognitive impairment related to a cerebral aneurysm and repair. Two patients had histories of bipolar I disorder, and two had depression. Four were on other medications that can cause mania (antidepressants, carbidopa/levodopa). Mania developed in most patients within 1 week of donepezil initiation, and resolved in most within 1 week of discontinuation. Our patient resembled previous reported cases wherein she was elderly, had vascular dementia, and developed mania within days of starting donepezil. It is unclear how donepezil may induce mania; one possibility is an increase in acetylcholine leading to changes in norepinephrine, dopamine, serotonin, or other neurotransmitters.5 Our case and those previously reported suggest that donepezil could precipitate mania in the context of cerebrovascular or other brain diseases, mood disorders, and/or treatment with other medications that can cause mania.