MEMANTINE HYDROCHLORIDE

Memantine is a N-methyl-D-aspartate (NMDA) receptor antagonist, that stimulates dopamine release. Memantine hydrochloride (1-amino3, 5-dimethyladamantane hydrochloride) is a tricyclic amine chemically and pharmacologically related to the anti-viral prototype amantadine and its α-methyl derivative rimantadine.N-Methyl-D-Aspartic Acid

Memantine is used in Parkinson’s disease and movement disorders. Memantine hydrochloride is currently known as the latest treatment for moderate-to-severe Alzheimer disease (AD). The drug acts by noncompetitively binding to the N-methyl d-aspartate (NMDA) receptors of neurons in brain tissue to prevent overstimulation by glutamate. When this excitatory neurotransmitter over activates NMDA receptors in a tonic manner, an excessive influx of neurotoxic calcium ions follows. The resultant excitotoxicity may play a role in the impairment of memory and cognition in AD. Because memantine has a low-to-moderate affinity for NMDA receptors, it does not seem to block normal glutamate transmission; rather, it reduces abnormal neurotransmitter-mediated activation of the receptors, thereby potentially reducing excitotoxic neuronal damage. This form of neuroprotection may explain the improved cognition in patients with AD.