Donepezil is a reversible, centrally-acting acetylcholinesterase inhibitor used in the treatment of mild to moderate symptoms of dementia associated with Alzheimer's disease. in recent years, there has been emerging evidence of its use in other conditions, such as Lewy Body dementia and autism. However, there have been few reports of the use of Donepezil to treat depression in the absence of cognitive impairment.

This is a case report of a 62-year old female with a long-standing history of major depressive disorder with no history of cognitive impairment, who failed to respond to antidepressants with augmentation therapy including antipsychotics, lithium and methylphenidate; but eventually improved on Donepezil.

A then-56-year old Chinese lady diagnosed with major depressive disorder, was treated with several antidepressants with poor response. Despite augmentation with dual antidepressants, antipsychotics, methylphenidate and lithium, her symptoms of avolition, depressed mood and irritability persisted. After 4 years of antidepressant treatment, she was started on donepezil 5 mg. Within a month of augmentation, significant improvement in symptoms were reported, notably in mood and volition, and the patient was able to engage in an active and meaningful lifestyle of semblance to her pre-morbid mental state.

This case highlights the possibility of Donepezil being used as an adjunctive therapy in major depressive disorder, even in the absence of cognitive impairment. Future studies to investigate the use of Donepezil may therefore be worthwhile to explore its use in this population of patients.