Skeletal myoclonus in olivopontocerebellar atrophy: treatment with trihexyphenidyl.

We studied two patients with nonfamilial olivopontocerebellar atrophy with skeletal myoclonus. Palatal or skeletal myoclonus is probably not a coincidental finding but another manifestation of the underlying disease. In both cases, the myoclonus was suppressed by administration of trihexyphenidyl, indicating a cholinergic disorder.