Obsessive-compulsive disorder induced by donepezil in a patient with Alzheimer's disease.

Background: Donepezil, an acetylcholinesterase inhibitor commonly used to treat Alzheimer's disease (AD), is generally well tolerated. There have been no previous reports on donepezil-induced obsessive-compulsive disorder (OCD).

Case Presentation: The patient, a retired man in his 70s diagnosed with AD, displayed OCD symptoms following donepezil initiation, exacerbating post-stroke-specifically, a cerebral infarction in the right posterior limb of the internal capsule.