Cholinesterase inhibitors and affective symptoms: A case report on long-term donepezil use in Alzheimer's and late onset of manic symptoms

Cholinesterase inhibitors, possibly have a role in the treatment of disorder involving the neuro cognition. Cholinesterase inhibitors like donepezil has been approved by Food and Drug Administration for mild moderate and sever dementia in Alzheimer s disease. Here we present a case report of a 92 year-old Caucasian female with Alzheimer's dementia with no personal or family history of psychiatric disorder presented with symptoms of pressured speech, flight of ideas, grandiosity, paranoia, and she endorsed euphoric mood. Weeks prior to presentation, patient had depressive symptoms. Patient received Donepezil 10mg daily and memantine 10mg twice daily for many months. Behavioral symptoms had been unsuccessfully treated with quetiapine 25mg PO three times daily. Donepezil was discontinued with all other medications unchanged. Behavior rapidly improved with resolution of affective symptoms. Donepezil is associated with the early mania and rare cases of late onset mania. Exact mechanism is still unclear. This case report hopes to add to the literature and to make consultation psychiatrists aware of this possible adverse effect of this class of medications.