AMANTADINE HYDROCHLORIDE TREATMENT IN HEREDODEGENERATIVE ATAXIAS - A DOUBLE-BLIND-STUDY

Objective-A group of 27 patients with Friedreich's ataxia and another group of 30 patients with olivopontocerebellar atrophies were each ran domly divided into two subgroups, one receiving placebo and the other amantadine hydrochloride (AH; 200 mg daily) for three to four months. Methods-The effect of double blind treatment was evaluated by simple v isual and auditory reaction time (RT) and movement time (MT) for both right and left hands. Results-The subgroup with olivopontocerebellar a trophies receiving AH showed significant improvement on seven out of e ight variables studied by analysis of covariance. In patients with Fri edreich's ataxia, improvement was definitely less. Treatment remained contraindicated for those with cardiomyopathies or drug intolerance. C onclusion-The rationale of AH use in heredodegenerative ataxias can be explained by its replacement effect (dopamine release) and by direct involvement of N-methyl-D-aspartate (NMDA) in glutamate mediated neuro toxicity in cerebellar granular cells; memantine, an AH analogue, is a potent blocker of NMDA receptors.