Product Overview
【Drug Name】
Generic Name: Donepezil Hydrochloride Tablets
Brand Name: Ares
English Name: Donepezil Hydrochloride Tablets
Pinyin: Yansuan Duonaipaiqi Pian
【Ingredients】
Donepezil hydrochloride. Chemical Name: ()2,3-dihydro-5,6-dimethoxy-2-{[(1-phenylmethyl)-4-piperidinyl]methyl}-1H-indene-1-one hydrochloride.
【Appearance】
Film-coated tablets, white after removing the film coating.
【Indications】
For the treatment of mild to moderate Alzheimer's disease symptoms.
【Dosage and Administration】
Oral administration. The initial dose is 5 mg (1 tablet) once daily at bedtime; maintain the initial dose for at least one month before increasing the dose to 10 mg (2 tablets) once daily, depending on the therapeutic effect. The maximum recommended dose is 10 mg daily. Doses greater than 10 mg daily have not been clinically studied. After treatment is discontinued, the efficacy of donepezil hydrochloride gradually diminishes, and there is no rebound effect upon discontinuation. Elimination of donepezil hydrochloride is unaffected in patients with renal insufficiency or mild to moderate hepatic impairment; therefore, similar dosage regimens can be used in these patients, or as directed by a physician.
【Adverse Reactions】
Common adverse reactions include nausea, diarrhea, insomnia, vomiting, muscle cramps, weakness, fatigue, and decreased appetite. Symptoms are usually mild and transient, requiring no dose adjustment, and symptoms may subside with continued use. Less common adverse reactions include headache, dizziness, mental confusion (hallucinations, irritability, aggressive behavior), weight loss, decreased vision, chest pain, arthralgia, depression, vivid dreams, somnolence, new neurological symptoms, rash, stomach pain, gastrointestinal disturbances, and frequent or irregular urination. Rare adverse reactions have been reported including syncope, bradycardia or arrhythmia, sinoatrial block, atrioventricular block, heart murmur, seizures, or melena.
【Contraindications】
Donepezil hydrochloride is contraindicated in patients with a history of hypersensitivity to donepezil hydrochloride, piperidine derivatives, or excipients in the formulation.
【Precautions】
Donepezil hydrochloride treatment should be initiated and supervised by a physician experienced in the diagnosis and treatment of Alzheimer's dementia. Diagnosis should be made according to recognized criteria (e.g., DSMIV, ICD10). Donepezil treatment should only be initiated when the patient has a reliable caregiver who can regularly monitor the patient's medication intake. Treatment can continue as long as the benefit to the patient persists. Therefore, the clinical efficacy of donepezil should be reassessed periodically. Treatment should be discontinued when the benefit is no longer present. Individual patient responses to donepezil are unpredictable. The effects of donepezil hydrochloride on patients with severe Alzheimer's dementia, other types of dementia, or other types of memory impairment (e.g., age-related cognitive decline) have not been fully observed. Anesthesia: Donepezil hydrochloride is a cholinesterase inhibitor; anesthesia may enhance the muscle relaxant effects of succinylcholine-based drugs. Cardiovascular System: Cholinesterase inhibitors can have a vagal effect on heart rate (e.g., bradycardia) due to their pharmacological action. Patients with sick sinus syndrome or other supraventricular conduction disorders should be monitored with particular care. There have been reports of syncope and seizures. Patients who may have heart block or sinus arrest should be closely monitored. Digestive System: Patients at increased risk of peptic ulcer disease, such as those with a history of peptic ulcer disease or those using nonsteroidal anti-inflammatory drugs (NSAIDs), should be monitored for symptoms. However, in clinical trials of donepezil hydrochloride, no increase in the incidence of peptic ulcers or gastrointestinal bleeding was observed compared to placebo. Genitourinary System: Cholinergic drugs can cause bladder obstruction, but this effect was not observed in clinical trials of donepezil hydrochloride. Nervous System: Cholinergic effects may cause grand mal seizures. However, seizures can also be a manifestation of Alzheimer's disease. Cholinergic drugs may exacerbate or induce extrapyramidal symptoms. Respiratory System: Due to its cholinergic effects, caution should be exercised in patients with a history of asthma or obstructive pulmonary disease. Concomitant use with other acetylcholinesterase inhibitors, cholinergic agonists, or antagonists should be avoided when taking donepezil hydrochloride. Liver function abnormalities, including hepatitis, are rarely reported after taking donepezil hydrochloride; however, if liver function abnormalities occur, discontinuation of the drug should be considered. If patients experience hallucinations, irritability, or aggressive behavior, dosage reduction or discontinuation of treatment should be considered. Effects on Driving and Operating Machinery: Alzheimer's dementia may impair the ability to drive or operate machinery. Additionally, donepezil can cause weakness, dizziness, and muscle spasms, primarily at the start of treatment or when increasing the dosage. The ability of Alzheimer's dementia patients taking donepezil to continue driving or operating complex machinery should be routinely assessed by their treating physician.
【Special Populations】
Precautions for Children: This product is not recommended for children.
Precautions during pregnancy and lactation:
1. Pregnancy: Teratogenicity studies conducted in pregnant rats at approximately 80 times the human dose and in rabbits at 50 times the human dose showed no teratogenicity. However, in pregnant rats at 50 times the human dose, administration from day 17 of gestation to day 20 postpartum resulted in a slight increase in stillbirths and a slight decrease in pup survival rate at day 4 postpartum. No adverse effects were observed at the next lower dose, approximately 15 times the human dose. Donepezil should not be used during pregnancy.
2. Lactation: It is unclear whether donepezil hydrochloride is excreted in breast milk; no studies have been conducted in lactating women. Therefore, women taking donepezil should not breastfeed.
Precautions for the elderly: Refer to section 1 of "Dosage and Administration".
【Drug Interactions】
Inducers of CYP3A4 and CYP2D6 isoenzymes, such as phenytoin sodium, carbamazepine, dexamethasone, rifampin, and phenobarbital, can increase the clearance of this product. Ketoconazole and quinidine, inhibitors of the CYP3A4 and CYP2D6 isoenzymes, inhibit the metabolism of this product. No interference with the metabolism of theophylline, cimetidine, warfarin, or digoxin was found. 4. This product may affect drugs with anticholinergic activity.
【Pharmacological Action】
Pharmacological Action: The pathogenesis of cognitive impairment in Alzheimer's disease is currently believed to be partly related to the decline in cholinergic neurotransmission function. Donepezil hydrochloride may exert its therapeutic effect by enhancing the function of cholinergic neurons. It reversibly inhibits the hydrolysis of acetylcholine by acetylcholinesterase, thereby increasing the concentration of acetylcholine. Based on the above mechanism of action, it is speculated that as the disease progresses, the number of functionally intact cholinergic neurons gradually decreases, and the effect of donepezil may weaken. Currently, there is no evidence that donepezil can alter the basic course of dementia. Toxicological Studies: Reproductive toxicity: In rats administered donepezil 10 mg/kg/day (approximately 8 times the maximum recommended human dose based on body surface area) did not affect fertility. In pregnant rats and rabbits, administration of donepezil at 16 and 10 mg/kg/day (approximately 13 and 16 times the maximum recommended human dose based on body surface area, respectively) showed no significant teratogenic effects. In another study, rats administered donepezil at 10 mg/kg/day (approximately 8 times the maximum recommended human dose based on body surface area) from day 17 of gestation to day 20 postpartum resulted in a slight increase in stillbirths and a slight decrease in offspring survival rate within 4 days postpartum. Genotoxicity: Donepezil showed no mutagenicity in the Ames bacteria reverse mutation assay. In the Chinese hamster lung cell chromosomal aberration assay, donepezil induced cleavage. Donepezil did not induce cleavage in the mouse micronucleus assay. Carcinogenicity: There is currently no data on the carcinogenicity of donepezil.
【Storage】
Store in a tightly closed container in a cool, dry place.
【Specifications】
5mg
【Packaging Specifications】
5mg*7 tablets/box
【Shelf Life】
24 months
【Approval Number】
National Drug Approval Number H20030583
【Manufacturer】
Company Name: Shaanxi Fangzhou Pharmaceutical Co., Ltd.
