DRUG DESCRIPTION. NAMENDA XR is an orally active NMDA receptor antagonist. The chemical name for memantine hydrochloride is 1-amino-3,5-dimethyladamantane hydrochloride with the following structural formula: The molecular formula is C12H21Nâ¢HCl and the molecular weight is 215.76.
There are three main parts to the ear, including the inner ear, middle ear and outer ear. In order for hearing to occur, there is a sequence of actions that must occur to transform waves of sound in the air into electrical impulses. These impulses are transmitted to the brain by the auditory (hearing) nerve.
These structures transmit sound vibrations to the inner ear. In so doing, they act as a transformer, converting sound vibrations in the external ear canal into fluid waves in the inner ear. The inner ear chamber contains tiny hearing and balance nerve endings bathed in fluid. The inner ear is a delicate, tissue-lined sense organ, which is encased in an outer hard bony shell.