Management of motor side effects of chronic levodopa therapy

The enthusiasm generated by the dramatic clinical response of parkinsonism to levodopa therapy has been blunted by the emergence of side effects related to chronic use of the drug. Levodopa-induced dyskinesias are thought to be due to striatal dopamine-receptor hypersensitivity as a result of chronic and excessive dopamine agonism. The daily dose of levodopa should be as low as possible and when dyskinesias develop, the dosage of both levodopa and anticholinergic agents should be reduced. Clinical oscillations, due to a variety of factors, are more difficult to control. More frequent and smaller doses of levodopa, drug holidays, and the use of amantadine or dopamine agonists may be helpful.