Donepezil hydrochloride can be taken for a long time, if the patient is diagnosed with Alzheimer’s disease, the drug can be taken for life, it is mainly used for the treatment of mild to moderate Alzheimer’s-type dementia, which can alleviate the symptoms and slow down the progress of the disease to a certain extent. Its pharmacological effect is mainly through the enhancement of cholinergic nerve function and play a therapeutic role, it can inhibit the hydrolysis of acetylcholine by acetylcholinesterase, thus increasing the concentration of acetylcholine, with the progression of Alzheimer’s disease, cholinergic neurons continue to apoptosis, the effect of Donepezil will be weakened, so for the late stage of Alzheimer’s disease its efficacy is not very good. This drug’s common adverse reactions to gastrointestinal symptoms, mainly nausea, vomiting, diarrhea, also has an effect on the nervous system, sometimes leading to insomnia, fatigue, lethargy, muscle spasms, etc., but the adverse reactions are mild, do not have to adjust the dosage, and can be slowly relieved after the medication is adapted to.