Parasomnias are any undesirable physical events or experiences that happen during falling asleep, staying asleep or during arousals from sleep. Parasomnias are classified primarily based on the stage of sleep from which they originate i.e. NREM or REM sleep and by the nature of symptoms, i.e. sleep terrors, sleep walking, sleep eating, etc. These disorders vary both in frequency and severity and range from relatively benign events such as occasional episode of sleep paralysis to potentially serious and sometimes life-threatening events such as REM sleep behavior disorder. Parasomnias are also considered to be automatisms since the subjects sometimes do not have conscious awareness during these episodes resulting in some medico-legal consequences. Parasomnias can significantly affect the quality of sleep resulting in daytime impairments and they can also affect sleep and safety of the bed-partners. However, a thorough clinical assessment, appropriate tests where indicated, and judicious use of medications can help a vast majority of patients with parasomnia disorders.
