Treatment of Dystonia with Tetrahydrobiopterin

Abstract

To the Editor: The variety of disorders with dystonia exceeds that of other forms of impaired motor control. Dystonic patients have involuntary, sustained muscle contractions and postures that can be extremely disabling. Certain dystonic conditions, such as those resulting from the wearing-off of anti-parkinsonism medication or the extrapyramidal effects of Wilson's disease, have more or less defined causes. However, the majority of dystonias, whether hereditary or sporadic, have no identifiable pathophysiology other than the troubling symptoms themselves.¹ The most promising therapeutic approaches have used the same pharmacologic interactions that have been successful in treating parkinsonism. Dopaminomimetic agents² or antagonism of . . .