We used transcranial magnetic stimulation (TMS) in patients with juvenile myoclonic epilepsy (JME) and healthy controls to characterise motorcortical excitability in the morning as compared to the evening. Intra- and interindividual comparisons in JME-patients and controls showed no significant differences of any TMS parameter. The expected rise of the resting motor thresholds (RMT) in JME-patients taking anticonvulsants could not be detected which may indicate a decreased RMT in JME-patients.