[Pronounced hypersomnia in a 13-year-old patient with periodic leg movements]

We report on a rare case of a thirteen-year old female with excessive daytime somnolence, which was caused by periodic leg movement. This underlines the necessity first to consider this diagnosis and second to record unconditionally the EMG derivation at minimum of the tibialis muscles in all patients with hypersomnolence. Even if carbamazepine is not the treatment of choice, in this case it was of remarkable effect.