<prompt> What are the clinical uses of AmantadineProphylaxis and treatment of influenza ATreatment of Parkinsons symptomsTreatment of drug induced extra pyramidal symptomsAll of the above  <response>: GLUTAMATE NMDA receptor ANTAGONISTDopamine facilitator Amantadine Developed as an antiviral drug for prophylaxis of influenza A2, it was found serendipitiously to benefit parkinsonism. Mech of action:- Amantadine promotes presynaptic synthesis and release of DA in the brain and has anticholinergic propey. These were believed to explain all its beneficial effect in parkinsonism. However, anantagonistic action on NMDA type of glutamate receptors, through which the striatal dopaminergic system exes its influence is now considered to bemore impoant. Side effects:- Insomnia, restlessness, confusion, nightmares, anticholinergic effects and rarely hallucinations. A characteristic side effect due to local release of CAs resulting in postcapillary vasoconstriction is livedo reticularis bluish discolouration and edema of ankles. Ref:- kd tripathi; pg num:-432,433 