Product Information
Registration Status: ActiveADMENTA 10 FILM COATED TABLET 10 mg is approved to be sold in Singapore with effective from 2019-01-09. It is marketed by RANBAXY (MALAYSIA) SDN. BHD., with the registration number of SIN15609P.
This product contains Memantine 10mg in the form of TABLET, FILM COATED. It is approved for ORAL use.
This product is manufactured by SUN PHARMACEUTICAL INDUSTRIES LIMITED in INDIA.
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.
Description
Memantine is an amantadine derivative with low to moderate-affinity for NMDA receptors. It is a noncompetitive NMDA receptor antagonist that binds preferentially to NMDA receptor-operated cation channels. It blocks the effects of excessive levels of glutamate that may lead to neuronal dysfunction. It is under investigation for the treatment of Alzheimer's disease, but there has been no clinical support for the prevention or slowing of disease progression.
Indication
For the treatment of moderate to severe dementia of the Alzheimer's type.
Mechanism of Action
Memantine exerts its action through uncompetitive NMDA receptor antagonism, binding preferentially to the NMDA receptor-operated cation channels. Prolonged increased levels of glutamate in the brain of demented patients are sufficient to counter the voltage-dependent block of NMDA receptors by Mg2+ ions and allow continuous influx of Ca2+ ions into cells, ultimately resulting in neuronal degeneration. Studies suggest that memantine binds more effectively than Mg2+ ions at the NMDA receptor, and thereby effectively blocks this prolonged influx of Ca2+ ions through the NMDA channel whilst preserving the transient physiological activation of the channels by higher concentrations of synaptically released glutamate. Thus memantine protects against chronically elevated concentrations of glutamate. Memantine also has antagonistic activity at the type 3 serotonergic (5-HT3) receptor with a potency that is similar to that at the NMDA receptor, and lower antagonistic activity at the nicotinic acetylcholine receptor. This drug has no affinity for γ-aminobutyric acid (GABA), benzodiazepine, dopamine, adrenergic, histamine, or glycine receptors or for voltage-dependent calcium, sodium, or potassium channels.
Pharmacokinetics
- Absorption
- Well absorbed orally with a bioavailability of approximately 100%. Peak plasma concentrations are reached in 3-7 hours. Food has no effect on absorption.
- Distribution
- * 9 to 11 L/kg
- Metabolism
- Excreted largely unchanged. About 20% is metabolized to 1-amino-3-hydroxymethyl-5-methyl-adamantane and 3-amino-1-hydroxy-5,7-dimethyl-adamantane.
- Elimination
Toxicity
Side effects include pain, abnormal crying, leg pain, fever, increased apetite. Adverse drug reactions include: dizziness, confusion, headache, hallucinations, tiredness. Less common side effects include: vomiting, anxiety, hypertonia, cystitis, and increased libido. Doses of up to 400 mg have been tolerated.
Active Ingredient/Synonyms
1-Amino-3,5-dimethyladamantane | 1,3-Dimethyl-5-adamantanamine | 3,5-Dimethyl-1-adamantanamine | 3,5-Dimethyl-1-aminoadamantane | 3,5-Dimethyltricyclo(3.3.1.1(3,7))decan-1-amine | Memantina | Memantine | Memantinum | Memantine |
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.