donepezil

Donepezil is a prescription medication used to treat the symptoms of Alzheimer's disease. It is a reversible acetylcholinesterase inhibitor that increases acetylcholine levels in the brain and is marketed under brand names such as Aricept and Aricept ODT. It is taken orally in tablet or orally disintegrating tablet forms.

Mechanism of action: Donepezil inhibits the enzyme acetylcholinesterase, slowing the breakdown of acetylcholine at cholinergic synapses in the central nervous system. This can help support cognition and daily function in some patients with Alzheimer's disease. It does not cure the disease or halt its progression.

Indications and efficacy: Donepezil is approved for mild, moderate, and severe Alzheimer's disease. Clinical effects are typically modest and vary among individuals; benefits may include improved cognition or function for a period of time in some patients, with symptoms often returning to baseline if the medication is stopped.

Dosing and administration: The usual starting dose is 5 mg once daily at bedtime. After 4–6 weeks, the dose may be increased to 10 mg once daily. For some patients with severe disease who have been stabilized on 10 mg daily, a higher dose of 23 mg once daily may be considered, but it carries a higher risk of adverse effects and requires careful medical supervision.

Safety and precautions: Common adverse effects include nausea, vomiting, diarrhea, insomnia, muscle cramps, weight loss, and fatigue. Bradycardia, fainting, and falls can occur, particularly in older adults or those with cardiac disease. Use with anticholinergic medicines or other cholinesterase inhibitors can affect efficacy or safety. Donepezil should be used under medical supervision, with monitoring for tolerability and drug interactions.