Donepezil is primarily used for the treatment of dementia associated with Alzheimer's disease. It is an FDA-approved medication used to treat mild, moderate, and severe Alzheimer's dementia. Donepezil works by increasing the amount of acetylcholine, a chemical in the brain that is typically reduced in people with Alzheimer's, which helps improve cognition, memory, attention, and the ability to perform daily activities. While it does not cure Alzheimer's disease or stop its progression, it can alleviate symptoms and improve mental function and behavior. Besides Alzheimer's disease, donepezil is also used off-label for other types of dementia, including Lewy body dementia, vascular dementia, and dementia associated with Parkinson's disease. It has shown some benefits in improving cognitive function and behavior in these conditions as well. Donepezil is available in oral tablet forms and as a transdermal patch for patients who may have difficulty swallowing. It is generally taken once daily, often in the evening. In summary, donepezil is used to help manage symptoms of dementia, especially in Alzheimer's disease, by improving cognitive function and daily functioning abilities.