Product Information
Registration Status: ActiveSIN09957P
ARICEPT TABLET 5mg is approved to be sold in Singapore with effective from 1998-08-31. It is marketed by EISAI (SINGAPORE) PTE LTD, with the registration number of SIN09957P.
This product contains Donepezil 5mg in the form of TABLET, FILM-COATED. It is approved for ORAL use.
This product is manufactured by EISAI TAIWAN INC in TAIWAN.
It is a Prescription Only Medicine that can only be obtained from a doctor or a dentist, or a pharmacist with a prescription from a Singapore-registered doctor or dentist.
Product Reference
Important Note: For generic product, the SPC/PIL provided may not be brand specific.
{{/items}} {{^items}}Description
Donepezil (Aricept), is a centrally acting reversible acetyl cholinesterase inhibitor. Its main therapeutic use is in the treatment of Alzheimer's disease where it is used to increase cortical acetylcholine. Donepezil is postulated to exert its therapeutic effect by enhancing cholinergic function. This is accomplished by increasing the concentration of acetylcholine through reversible inhibition of its hydrolysis by acetylcholinesterase. If this proposed mechanism of action is correct, donepezil's effect may lessen as the disease process advances and fewer cholinergic neurons remain functionally intact. Donepezil has been tested in other cognitive disorders including Lewy body dementia and Vascular dementia, but it is not currently approved for these indications. Donepezil has also been studied in patients with Mild Cognitive Impairment, schizophrenia, attention deficit disorder, post-coronary bypass cognitive impairment, cognitive impairment associated with multiple sclerosis, and Down syndrome.
Indication
For the palliative treatment of mild to moderate dementia of the Alzheimer's type.
Mechanism of Action
Donepezil is a piperidine derivative that is a centerally active, reversible inhibitor of acetylcholinesterase. This drug is structurally unrelated to other anticholinesterase agents. Donepezil's proposed mechanism of action involves the reversible inhibition of cholinesterases (eg. acetylcholinesterase), which prevents the hydrolysis of acetycholine, and leads to an increased concentration of acetylcholine at cholinergic synapses. Evidence suggests that the anticholinesterase activity of donepezil is relatively specific for acetylcholinesterase in the brain.
Pharmacokinetics
- Absorption
- Donepezil is well absorbed with a relative oral bioavailability of 100% and reaches peak plasma concentrations in 3 to 4 hours.
- Distribution
- * 12 L/kg
- Metabolism
- Donepezil is metabolized by CYP 450 isoenzymes 2D6 and 3A4 in the liver and also undergoes glucuronidation. The main metabolite, 6-O-desmethyl donepezil, has been reported to inhibit AChE to the same extent as donepezil in vitro.
- Elimination
Clearance
* apparent plasma cl=0.13 L/hr/kg
Toxicity
Symptoms of overdose include severe nausea, vomiting, salivation, sweating, bradycardia, hypotension, respiratory depression, collapse and convulsions. Increasing muscle weakness is a possibility and may result in death if respiratory muscles are involved.
Active Ingredient/Synonyms
Domepezil | Donepezil | Donepezilo | Donepezilum | Donepezil |
Source of information: Drugbank (External Link). Last updated on: 3rd July 18. *Trade Name used in the content below may not be the same as the HSA-registered product.