Amantadine for the treatment of levodopa-induced dyskinesias in Parkinson's disease.

The development of dyskinesias is a common side effect during chronic levod opa therapy in parkinsonian patients. Recent reports suggest that amantadin e, a drug with well known antiparkinsonian activity, is effective in the tr eatment of this complication. In order to evaluate its usefulness we conduc ted an open label, prospective and longitudinal study in 26 patients with P arkinson's disease (PD) on chronic levodopa therapy who presented peaks of dose dyskinesias. After 3 weeks' treatment dyskinesia severity was reduced by 70% (p < 0.0001) on the I SAPD scale and by 68.8% (p < 0.0002) on the UP DRS IV subscale. Patients were later evaluated every 45 days showing persis tent drug benefit during follow-up ranging from 2 to 11 months (mean 6.5 mo nths). One third of our series presented unwanted effects which were only s evere enough in 2 cases to discontinue treatment. In the others, side effec ts were transient or readily abated with amantadine dose reduction. Our fin dings support amantadine as a safe and useful drug to treat levodopa-induce d dyskinesias which on occasion prove as disabling as PD itself. Treatment with amantadine should routinely be considered before indicating pallidotom y for levodopa-induced dyskinesias.