Myoclonus and seizures in a patient with parkinsonism: induction by levodopa and its confirmation on SEPs.

A 68-year-old woman with parkinsonism showed cortical myoclonus and seizures under antiparkinsonian medication. Myoclonus was induced and enhanced by L-dopa, developing into generalized seizures. EEG was abnormal and somatosensory-evoked potentials (SEPs) showed giant SEPs, transcortical reflex (C reflex) and jerk locked potentials. Myoclonus and seizures disappeared after discontinuation of L-dopa and the introduction of valproate sodium (VPA). We described the occurrence of L-dopa-induced myoclonus and seizures in a case of parkinsonism with its SEPs findings.